Best exchange rates Solid Trust Pay USD to Bitcoin ...

Bitcoin to Solid Trust Pay - Exchange Bitcoin to STP

submitted by jontivu007 to u/jontivu007 [link] [comments]

Comparison between Avalanche, Cosmos and Polkadot

Comparison between Avalanche, Cosmos and Polkadot
Reposting after was mistakenly removed by mods (since resolved - Thanks)
A frequent question I see being asked is how Cosmos, Polkadot and Avalanche compare? Whilst there are similarities there are also a lot of differences. This article is not intended to be an extensive in-depth list, but rather an overview based on some of the criteria that I feel are most important.
For better formatting see https://medium.com/ava-hub/comparison-between-avalanche-cosmos-and-polkadot-a2a98f46c03b
https://preview.redd.it/e8s7dj3ivpq51.png?width=428&format=png&auto=webp&s=5d0463462702637118c7527ebf96e91f4a80b290

Overview

Cosmos

Cosmos is a heterogeneous network of many independent parallel blockchains, each powered by classical BFT consensus algorithms like Tendermint. Developers can easily build custom application specific blockchains, called Zones, through the Cosmos SDK framework. These Zones connect to Hubs, which are specifically designed to connect zones together.
The vision of Cosmos is to have thousands of Zones and Hubs that are Interoperable through the Inter-Blockchain Communication Protocol (IBC). Cosmos can also connect to other systems through peg zones, which are specifically designed zones that each are custom made to interact with another ecosystem such as Ethereum and Bitcoin. Cosmos does not use Sharding with each Zone and Hub being sovereign with their own validator set.
For a more in-depth look at Cosmos and provide more reference to points made in this article, please see my three part series — Part One, Part Two, Part Three
(There's a youtube video with a quick video overview of Cosmos on the medium article - https://medium.com/ava-hub/comparison-between-avalanche-cosmos-and-polkadot-a2a98f46c03b)

Polkadot

Polkadot is a heterogeneous blockchain protocol that connects multiple specialised blockchains into one unified network. It achieves scalability through a sharding infrastructure with multiple blockchains running in parallel, called parachains, that connect to a central chain called the Relay Chain. Developers can easily build custom application specific parachains through the Substrate development framework.
The relay chain validates the state transition of connected parachains, providing shared state across the entire ecosystem. If the Relay Chain must revert for any reason, then all of the parachains would also revert. This is to ensure that the validity of the entire system can persist, and no individual part is corruptible. The shared state makes it so that the trust assumptions when using parachains are only those of the Relay Chain validator set, and no other. Interoperability is enabled between parachains through Cross-Chain Message Passing (XCMP) protocol and is also possible to connect to other systems through bridges, which are specifically designed parachains or parathreads that each are custom made to interact with another ecosystem such as Ethereum and Bitcoin. The hope is to have 100 parachains connect to the relay chain.
For a more in-depth look at Polkadot and provide more reference to points made in this article, please see my three part series — Part One, Part Two, Part Three
(There's a youtube video with a quick video overview of Polkadot on the medium article - https://medium.com/ava-hub/comparison-between-avalanche-cosmos-and-polkadot-a2a98f46c03b)

Avalanche

Avalanche is a platform of platforms, ultimately consisting of thousands of subnets to form a heterogeneous interoperable network of many blockchains, that takes advantage of the revolutionary Avalanche Consensus protocols to provide a secure, globally distributed, interoperable and trustless framework offering unprecedented decentralisation whilst being able to comply with regulatory requirements.
Avalanche allows anyone to create their own tailor-made application specific blockchains, supporting multiple custom virtual machines such as EVM and WASM and written in popular languages like Go (with others coming in the future) rather than lightly used, poorly-understood languages like Solidity. This virtual machine can then be deployed on a custom blockchain network, called a subnet, which consist of a dynamic set of validators working together to achieve consensus on the state of a set of many blockchains where complex rulesets can be configured to meet regulatory compliance.
Avalanche was built with serving financial markets in mind. It has native support for easily creating and trading digital smart assets with complex custom rule sets that define how the asset is handled and traded to ensure regulatory compliance can be met. Interoperability is enabled between blockchains within a subnet as well as between subnets. Like Cosmos and Polkadot, Avalanche is also able to connect to other systems through bridges, through custom virtual machines made to interact with another ecosystem such as Ethereum and Bitcoin.
For a more in-depth look at Avalanche and provide more reference to points made in this article, please see here and here
(There's a youtube video with a quick video overview of Avalanche on the medium article - https://medium.com/ava-hub/comparison-between-avalanche-cosmos-and-polkadot-a2a98f46c03b)

Comparison between Cosmos, Polkadot and Avalanche

A frequent question I see being asked is how Cosmos, Polkadot and Avalanche compare? Whilst there are similarities there are also a lot of differences. This article is not intended to be an extensive in-depth list, but rather an overview based on some of the criteria that I feel are most important. For a more in-depth view I recommend reading the articles for each of the projects linked above and coming to your own conclusions. I want to stress that it’s not a case of one platform being the killer of all other platforms, far from it. There won’t be one platform to rule them all, and too often the tribalism has plagued this space. Blockchains are going to completely revolutionise most industries and have a profound effect on the world we know today. It’s still very early in this space with most adoption limited to speculation and trading mainly due to the limitations of Blockchain and current iteration of Ethereum, which all three of these platforms hope to address. For those who just want a quick summary see the image at the bottom of the article. With that said let’s have a look

Scalability

Cosmos

Each Zone and Hub in Cosmos is capable of up to around 1000 transactions per second with bandwidth being the bottleneck in consensus. Cosmos aims to have thousands of Zones and Hubs all connected through IBC. There is no limit on the number of Zones / Hubs that can be created

Polkadot

Parachains in Polkadot are also capable of up to around 1500 transactions per second. A portion of the parachain slots on the Relay Chain will be designated as part of the parathread pool, the performance of a parachain is split between many parathreads offering lower performance and compete amongst themselves in a per-block auction to have their transactions included in the next relay chain block. The number of parachains is limited by the number of validators on the relay chain, they hope to be able to achieve 100 parachains.

Avalanche

Avalanche is capable of around 4500 transactions per second per subnet, this is based on modest hardware requirements to ensure maximum decentralisation of just 2 CPU cores and 4 GB of Memory and with a validator size of over 2,000 nodes. Performance is CPU-bound and if higher performance is required then more specialised subnets can be created with higher minimum requirements to be able to achieve 10,000 tps+ in a subnet. Avalanche aims to have thousands of subnets (each with multiple virtual machines / blockchains) all interoperable with each other. There is no limit on the number of Subnets that can be created.

Results

All three platforms offer vastly superior performance to the likes of Bitcoin and Ethereum 1.0. Avalanche with its higher transactions per second, no limit on the number of subnets / blockchains that can be created and the consensus can scale to potentially millions of validators all participating in consensus scores ✅✅✅. Polkadot claims to offer more tps than cosmos, but is limited to the number of parachains (around 100) whereas with Cosmos there is no limit on the number of hubs / zones that can be created. Cosmos is limited to a fairly small validator size of around 200 before performance degrades whereas Polkadot hopes to be able to reach 1000 validators in the relay chain (albeit only a small number of validators are assigned to each parachain). Thus Cosmos and Polkadot scores ✅✅
https://preview.redd.it/2o0brllyvpq51.png?width=1000&format=png&auto=webp&s=8f62bb696ecaafcf6184da005d5fe0129d504518

Decentralisation

Cosmos

Tendermint consensus is limited to around 200 validators before performance starts to degrade. Whilst there is the Cosmos Hub it is one of many hubs in the network and there is no central hub or limit on the number of zones / hubs that can be created.

Polkadot

Polkadot has 1000 validators in the relay chain and these are split up into a small number that validate each parachain (minimum of 14). The relay chain is a central point of failure as all parachains connect to it and the number of parachains is limited depending on the number of validators (they hope to achieve 100 parachains). Due to the limited number of parachain slots available, significant sums of DOT will need to be purchased to win an auction to lease the slot for up to 24 months at a time. Thus likely to lead to only those with enough funds to secure a parachain slot. Parathreads are however an alternative for those that require less and more varied performance for those that can’t secure a parachain slot.

Avalanche

Avalanche consensus scan scale to tens of thousands of validators, even potentially millions of validators all participating in consensus through repeated sub-sampling. The more validators, the faster the network becomes as the load is split between them. There are modest hardware requirements so anyone can run a node and there is no limit on the number of subnets / virtual machines that can be created.

Results

Avalanche offers unparalleled decentralisation using its revolutionary consensus protocols that can scale to millions of validators all participating in consensus at the same time. There is no limit to the number of subnets and virtual machines that can be created, and they can be created by anyone for a small fee, it scores ✅✅✅. Cosmos is limited to 200 validators but no limit on the number of zones / hubs that can be created, which anyone can create and scores ✅✅. Polkadot hopes to accommodate 1000 validators in the relay chain (albeit these are split amongst each of the parachains). The number of parachains is limited and maybe cost prohibitive for many and the relay chain is a ultimately a single point of failure. Whilst definitely not saying it’s centralised and it is more decentralised than many others, just in comparison between the three, it scores ✅
https://preview.redd.it/ckfamee0wpq51.png?width=1000&format=png&auto=webp&s=c4355f145d821fabf7785e238dbc96a5f5ce2846

Latency

Cosmos

Tendermint consensus used in Cosmos reaches finality within 6 seconds. Cosmos consists of many Zones and Hubs that connect to each other. Communication between 2 zones could pass through many hubs along the way, thus also can contribute to latency times depending on the path taken as explained in part two of the articles on Cosmos. It doesn’t need to wait for an extended period of time with risk of rollbacks.

Polkadot

Polkadot provides a Hybrid consensus protocol consisting of Block producing protocol, BABE, and then a finality gadget called GRANDPA that works to agree on a chain, out of many possible forks, by following some simpler fork choice rule. Rather than voting on every block, instead it reaches agreements on chains. As soon as more than 2/3 of validators attest to a chain containing a certain block, all blocks leading up to that one are finalized at once.
If an invalid block is detected after it has been finalised then the relay chain would need to be reverted along with every parachain. This is particularly important when connecting to external blockchains as those don’t share the state of the relay chain and thus can’t be rolled back. The longer the time period, the more secure the network is, as there is more time for additional checks to be performed and reported but at the expense of finality. Finality is reached within 60 seconds between parachains but for external ecosystems like Ethereum their state obviously can’t be rolled back like a parachain and so finality will need to be much longer (60 minutes was suggested in the whitepaper) and discussed in more detail in part three

Avalanche

Avalanche consensus achieves finality within 3 seconds, with most happening sub 1 second, immutable and completely irreversible. Any subnet can connect directly to another without having to go through multiple hops and any VM can talk to another VM within the same subnet as well as external subnets. It doesn’t need to wait for an extended period of time with risk of rollbacks.

Results

With regards to performance far too much emphasis is just put on tps as a metric, the other equally important metric, if not more important with regards to finance is latency. Throughput measures the amount of data at any given time that it can handle whereas latency is the amount of time it takes to perform an action. It’s pointless saying you can process more transactions per second than VISA when it takes 60 seconds for a transaction to complete. Low latency also greatly increases general usability and customer satisfaction, nowadays everyone expects card payments, online payments to happen instantly. Avalanche achieves the best results scoring ✅✅✅, Cosmos with comes in second with 6 second finality ✅✅ and Polkadot with 60 second finality (which may be 60 minutes for external blockchains) scores ✅
https://preview.redd.it/kzup5x42wpq51.png?width=1000&format=png&auto=webp&s=320eb4c25dc4fc0f443a7a2f7ff09567871648cd

Shared Security

Cosmos

Every Zone and Hub in Cosmos has their own validator set and different trust assumptions. Cosmos are researching a shared security model where a Hub can validate the state of connected zones for a fee but not released yet. Once available this will make shared security optional rather than mandatory.

Polkadot

Shared Security is mandatory with Polkadot which uses a Shared State infrastructure between the Relay Chain and all of the connected parachains. If the Relay Chain must revert for any reason, then all of the parachains would also revert. Every parachain makes the same trust assumptions, and as such the relay chain validates state transition and enables seamless interoperability between them. In return for this benefit, they have to purchase DOT and win an auction for one of the available parachain slots.
However, parachains can’t just rely on the relay chain for their security, they will also need to implement censorship resistance measures and utilise proof of work / proof of stake for each parachain as well as discussed in part three, thus parachains can’t just rely on the security of the relay chain, they need to ensure sybil resistance mechanisms using POW and POS are implemented on the parachain as well.

Avalanche

A subnet in Avalanche consists of a dynamic set of validators working together to achieve consensus on the state of a set of many blockchains where complex rulesets can be configured to meet regulatory compliance. So unlike in Cosmos where each zone / hub has their own validators, A subnet can validate a single or many virtual machines / blockchains with a single validator set. Shared security is optional

Results

Shared security is mandatory in polkadot and a key design decision in its infrastructure. The relay chain validates the state transition of all connected parachains and thus scores ✅✅✅. Subnets in Avalanche can validate state of either a single or many virtual machines. Each subnet can have their own token and shares a validator set, where complex rulesets can be configured to meet regulatory compliance. It scores ✅ ✅. Every Zone and Hub in cosmos has their own validator set / token but research is underway to have the hub validate the state transition of connected zones, but as this is still early in the research phase scores ✅ for now.
https://preview.redd.it/pbgyk3o3wpq51.png?width=1000&format=png&auto=webp&s=61c18e12932a250f5633c40633810d0f64520575

Current Adoption

Cosmos

The Cosmos project started in 2016 with an ICO held in April 2017. There are currently around 50 projects building on the Cosmos SDK with a full list can be seen here and filtering for Cosmos SDK . Not all of the projects will necessarily connect using native cosmos sdk and IBC and some have forked parts of the Cosmos SDK and utilise the tendermint consensus such as Binance Chain but have said they will connect in the future.

Polkadot

The Polkadot project started in 2016 with an ICO held in October 2017. There are currently around 70 projects building on Substrate and a full list can be seen here and filtering for Substrate Based. Like with Cosmos not all projects built using substrate will necessarily connect to Polkadot and parachains or parathreads aren’t currently implemented in either the Live or Test network (Kusama) as of the time of this writing.

Avalanche

Avalanche in comparison started much later with Ava Labs being founded in 2018. Avalanche held it’s ICO in July 2020. Due to lot shorter time it has been in development, the number of projects confirmed are smaller with around 14 projects currently building on Avalanche. Due to the customisability of the platform though, many virtual machines can be used within a subnet making the process incredibly easy to port projects over. As an example, it will launch with the Ethereum Virtual Machine which enables byte for byte compatibility and all the tooling like Metamask, Truffle etc. will work, so projects can easily move over to benefit from the performance, decentralisation and low gas fees offered. In the future Cosmos and Substrate virtual machines could be implemented on Avalanche.

Results

Whilst it’s still early for all 3 projects (and the entire blockchain space as a whole), there is currently more projects confirmed to be building on Cosmos and Polkadot, mostly due to their longer time in development. Whilst Cosmos has fewer projects, zones are implemented compared to Polkadot which doesn’t currently have parachains. IBC to connect zones and hubs together is due to launch Q2 2021, thus both score ✅✅✅. Avalanche has been in development for a lot shorter time period, but is launching with an impressive feature set right from the start with ability to create subnets, VMs, assets, NFTs, permissioned and permissionless blockchains, cross chain atomic swaps within a subnet, smart contracts, bridge to Ethereum etc. Applications can easily port over from other platforms and use all the existing tooling such as Metamask / Truffle etc but benefit from the performance, decentralisation and low gas fees offered. Currently though just based on the number of projects in comparison it scores ✅.
https://preview.redd.it/4zpi6s85wpq51.png?width=1000&format=png&auto=webp&s=e91ade1a86a5d50f4976f3b23a46e9287b08e373

Enterprise Adoption

Cosmos

Cosmos enables permissioned and permissionless zones which can connect to each other with the ability to have full control over who validates the blockchain. For permissionless zones each zone / hub can have their own token and they are in control who validates.

Polkadot

With polkadot the state transition is performed by a small randomly selected assigned group of validators from the relay chain plus with the possibility that state is rolled back if an invalid transaction of any of the other parachains is found. This may pose a problem for enterprises that need complete control over who performs validation for regulatory reasons. In addition due to the limited number of parachain slots available Enterprises would have to acquire and lock up large amounts of a highly volatile asset (DOT) and have the possibility that they are outbid in future auctions and find they no longer can have their parachain validated and parathreads don’t provide the guaranteed performance requirements for the application to function.

Avalanche

Avalanche enables permissioned and permissionless subnets and complex rulesets can be configured to meet regulatory compliance. For example a subnet can be created where its mandatory that all validators are from a certain legal jurisdiction, or they hold a specific license and regulated by the SEC etc. Subnets are also able to scale to tens of thousands of validators, and even potentially millions of nodes, all participating in consensus so every enterprise can run their own node rather than only a small amount. Enterprises don’t have to hold large amounts of a highly volatile asset, but instead pay a fee in AVAX for the creation of the subnets and blockchains which is burnt.

Results

Avalanche provides the customisability to run private permissioned blockchains as well as permissionless where the enterprise is in control over who validates the blockchain, with the ability to use complex rulesets to meet regulatory compliance, thus scores ✅✅✅. Cosmos is also able to run permissioned and permissionless zones / hubs so enterprises have full control over who validates a blockchain and scores ✅✅. Polkadot requires locking up large amounts of a highly volatile asset with the possibility of being outbid by competitors and being unable to run the application if the guaranteed performance is required and having to migrate away. The relay chain validates the state transition and can roll back the parachain should an invalid block be detected on another parachain, thus scores ✅.
https://preview.redd.it/li5jy6u6wpq51.png?width=1000&format=png&auto=webp&s=e2a95f1f88e5efbcf9e23c789ae0f002c8eb73fc

Interoperability

Cosmos

Cosmos will connect Hubs and Zones together through its IBC protocol (due to release in Q1 2020). Connecting to blockchains outside of the Cosmos ecosystem would either require the connected blockchain to fork their code to implement IBC or more likely a custom “Peg Zone” will be created specific to work with a particular blockchain it’s trying to bridge to such as Ethereum etc. Each Zone and Hub has different trust levels and connectivity between 2 zones can have different trust depending on which path it takes (this is discussed more in this article). Finality time is low at 6 seconds, but depending on the number of hops, this can increase significantly.

Polkadot

Polkadot’s shared state means each parachain that connects shares the same trust assumptions, of the relay chain validators and that if one blockchain needs to be reverted, all of them will need to be reverted. Interoperability is enabled between parachains through Cross-Chain Message Passing (XCMP) protocol and is also possible to connect to other systems through bridges, which are specifically designed parachains or parathreads that each are custom made to interact with another ecosystem such as Ethereum and Bitcoin. Finality time between parachains is around 60 seconds, but longer will be needed (initial figures of 60 minutes in the whitepaper) for connecting to external blockchains. Thus limiting the appeal of connecting two external ecosystems together through Polkadot. Polkadot is also limited in the number of Parachain slots available, thus limiting the amount of blockchains that can be bridged. Parathreads could be used for lower performance bridges, but the speed of future blockchains is only going to increase.

Avalanche

A subnet can validate multiple virtual machines / blockchains and all blockchains within a subnet share the same trust assumptions / validator set, enabling cross chain interoperability. Interoperability is also possible between any other subnet, with the hope Avalanche will consist of thousands of subnets. Each subnet may have a different trust level, but as the primary network consists of all validators then this can be used as a source of trust if required. As Avalanche supports many virtual machines, bridges to other ecosystems are created by running the connected virtual machine. There will be an Ethereum bridge using the EVM shortly after mainnet. Finality time is much faster at sub 3 seconds (with most happening under 1 second) with no chance of rolling back so more appealing when connecting to external blockchains.

Results

All 3 systems are able to perform interoperability within their ecosystem and transfer assets as well as data, as well as use bridges to connect to external blockchains. Cosmos has different trust levels between its zones and hubs and can create issues depending on which path it takes and additional latency added. Polkadot provides the same trust assumptions for all connected parachains but has long finality and limited number of parachain slots available. Avalanche provides the same trust assumptions for all blockchains within a subnet, and different trust levels between subnets. However due to the primary network consisting of all validators it can be used for trust. Avalanche also has a much faster finality time with no limitation on the number of blockchains / subnets / bridges that can be created. Overall all three blockchains excel with interoperability within their ecosystem and each score ✅✅.
https://preview.redd.it/ai0bkbq8wpq51.png?width=1000&format=png&auto=webp&s=3e85ee6a3c4670f388ccea00b0c906c3fb51e415

Tokenomics

Cosmos

The ATOM token is the native token for the Cosmos Hub. It is commonly mistaken by people that think it’s the token used throughout the cosmos ecosystem, whereas it’s just used for one of many hubs in Cosmos, each with their own token. Currently ATOM has little utility as IBC isn’t released and has no connections to other zones / hubs. Once IBC is released zones may prefer to connect to a different hub instead and so ATOM is not used. ATOM isn’t a fixed capped supply token and supply will continuously increase with a yearly inflation of around 10% depending on the % staked. The current market cap for ATOM as of the time of this writing is $1 Billion with 203 million circulating supply. Rewards can be earnt through staking to offset the dilution caused by inflation. Delegators can also get slashed and lose a portion of their ATOM should the validator misbehave.

Polkadot

Polkadot’s native token is DOT and it’s used to secure the Relay Chain. Each parachain needs to acquire sufficient DOT to win an auction on an available parachain lease period of up to 24 months at a time. Parathreads have a fixed fee for registration that would realistically be much lower than the cost of acquiring a parachain slot and compete with other parathreads in a per-block auction to have their transactions included in the next relay chain block. DOT isn’t a fixed capped supply token and supply will continuously increase with a yearly inflation of around 10% depending on the % staked. The current market cap for DOT as of the time of this writing is $4.4 Billion with 852 million circulating supply. Delegators can also get slashed and lose their DOT (potentially 100% of their DOT for serious attacks) should the validator misbehave.

Avalanche

AVAX is the native token for the primary network in Avalanche. Every validator of any subnet also has to validate the primary network and stake a minimum of 2000 AVAX. There is no limit to the number of validators like other consensus methods then this can cater for tens of thousands even potentially millions of validators. As every validator validates the primary network, this can be a source of trust for interoperability between subnets as well as connecting to other ecosystems, thus increasing amount of transaction fees of AVAX. There is no slashing in Avalanche, so there is no risk to lose your AVAX when selecting a validator, instead rewards earnt for staking can be slashed should the validator misbehave. Because Avalanche doesn’t have direct slashing, it is technically possible for someone to both stake AND deliver tokens for something like a flash loan, under the invariant that all tokens that are staked are returned, thus being able to make profit with staked tokens outside of staking itself.
There will also be a separate subnet for Athereum which is a ‘spoon,’ or friendly fork, of Ethereum, which benefits from the Avalanche consensus protocol and applications in the Ethereum ecosystem. It’s native token ATH will be airdropped to ETH holders as well as potentially AVAX holders as well. This can be done for other blockchains as well.
Transaction fees on the primary network for all 3 of the blockchains as well as subscription fees for creating a subnet and blockchain are paid in AVAX and are burnt, creating deflationary pressure. AVAX is a fixed capped supply of 720 million tokens, creating scarcity rather than an unlimited supply which continuously increase of tokens at a compounded rate each year like others. Initially there will be 360 tokens minted at Mainnet with vesting periods between 1 and 10 years, with tokens gradually unlocking each quarter. The Circulating supply is 24.5 million AVAX with tokens gradually released each quater. The current market cap of AVAX is around $100 million.

Results

Avalanche’s AVAX with its fixed capped supply, deflationary pressure, very strong utility, potential to receive air drops and low market cap, means it scores ✅✅✅. Polkadot’s DOT also has very strong utility with the need for auctions to acquire parachain slots, but has no deflationary mechanisms, no fixed capped supply and already valued at $3.8 billion, therefore scores ✅✅. Cosmos’s ATOM token is only for the Cosmos Hub, of which there will be many hubs in the ecosystem and has very little utility currently. (this may improve once IBC is released and if Cosmos hub actually becomes the hub that people want to connect to and not something like Binance instead. There is no fixed capped supply and currently valued at $1.1 Billion, so scores ✅.
https://preview.redd.it/mels7myawpq51.png?width=1000&format=png&auto=webp&s=df9782e2c0a4c26b61e462746256bdf83b1fb906
All three are excellent projects and have similarities as well as many differences. Just to reiterate this article is not intended to be an extensive in-depth list, but rather an overview based on some of the criteria that I feel are most important. For a more in-depth view I recommend reading the articles for each of the projects linked above and coming to your own conclusions, you may have different criteria which is important to you, and score them differently. There won’t be one platform to rule them all however, with some uses cases better suited to one platform over another, and it’s not a zero-sum game. Blockchain is going to completely revolutionize industries and the Internet itself. The more projects researching and delivering breakthrough technology the better, each learning from each other and pushing each other to reach that goal earlier. The current market is a tiny speck of what’s in store in terms of value and adoption and it’s going to be exciting to watch it unfold.
https://preview.redd.it/dbb99egcwpq51.png?width=1388&format=png&auto=webp&s=aeb03127dc0dc74d0507328e899db1c7d7fc2879
For more information see the articles below (each with additional sources at the bottom of their articles)
Avalanche, a Revolutionary Consensus Engine and Platform. A Game Changer for Blockchain
Avalanche Consensus, The Biggest Breakthrough since Nakamoto
Cosmos — An Early In-Depth Analysis — Part One
Cosmos — An Early In-Depth Analysis — Part Two
Cosmos Hub ATOM Token and the commonly misunderstood staking tokens — Part Three
Polkadot — An Early In-Depth Analysis — Part One — Overview and Benefits
Polkadot — An Early In-Depth Analysis — Part Two — How Consensus Works
Polkadot — An Early In-Depth Analysis — Part Three — Limitations and Issues
submitted by xSeq22x to CryptoCurrency [link] [comments]

Polkadot — An Early In-Depth Analysis — Part One — Overview and Benefits

Polkadot — An Early In-Depth Analysis — Part One — Overview and Benefits
Having recently researched Polkadot, as with other projects, I wanted to document what I had learnt, so that others may potential find it useful. Hopefully providing a balanced view, it will consist of three articles outlined below.
Part One — Polkadot Overview and Benefits (This article)
Part Two — In-Depth look at the Consensus
Part Three — Limitations and Issues
I will provide links throughout, providing reference to sections, as well as include a list of sources at the bottom of the article for further reading.
https://preview.redd.it/pr8hmkhhe6m51.png?width=700&format=png&auto=webp&s=58331d0411e684b4c511d59aeabeb789205d8a44

Overview

Frustrated with the slow development of Ethereum 2.0, Dr. Gavin Wood, co-founder of Ethereum and inventor of Solidity, left to begin work on Polkadot, a next generation scalable blockchain protocol that connects multiple specialised blockchains into one unified network. It achieves scalability through a sharding infrastructure with multiple blockchains running in parallel, called parachains, that connect to a central chain called the Relay Chain.
Whilst it shares some similarities with Ethereum 2.0, one key differentiator is that it uses heterogeneous sharding, where each parachains can be customised through the Substrate development framework, enabling them to be optimised for a specific use case and running in parallel rather than same across all shards. This is important as when it comes to blockchain architecture, one size does not fit all and all blockchains make trade-offs to support different features and use cases.
All parachains connect to the relay chain, which validates the state transition of connected parachains, providing shared state across the entire ecosystem. If the Relay Chain must revert for any reason, then all of the parachains would also revert. This is to ensure that the validity of the entire system can persist, and no individual part is corruptible. The shared state makes it so that the trust assumptions when using parachains are only those of the Relay Chain validator set, and no other. Since the validator set on the Relay Chain is expected to be secure with a large amount of stake put up to back it, it is desirable for parachains to benefit from this security.
This enables seamless interoperability between all parachains and parathreads using the Cross-chain Message Passing (XCMP) protocol, allowing arbitrary data — not just tokens — to be transferred across blockchains. Interoperability is also possible to other ecosystems through bridges, which are specifically designed parachains or parathreads that are custom made to interact with another ecosystem such as Ethereum, Bitcoin and Cosmos for example, enabling interoperability. Because these other ecosystems don’t use the same shared state of Polkadot, finality is incredibly important, because whilst the relay chain can roll back all the parachains, it can’t roll back the Ethereum or Bitcoin blockchains for example. This is discussed further in part three.
https://preview.redd.it/lmrz428je6m51.png?width=1000&format=png&auto=webp&s=237ad499f85e960ca50ca884234453ce283a60c0
The relay chain is responsible for the network’s shared security, consensus and cross-chain interoperability. It is secured by Validators and Nominators staking the native DOT tokens. Ultimately scalability for the ecosystem is determined by how scalable the relay chain can be. The number of parachains is determined by the number of validators on the relay chain. The hope is to reach 1000 validators, which would enable around 100 parachains. With each parachain being capable of around 1,000 transactions per second.
Nominators stake their DOT tokens with validators they trust, with the validators likely charging a small commission to cover running costs. If a validator is found to have performed misconduct a percentage of the their stake but also the nominators stake will be slashed depending upon the severity. For Level 4 security threats such as collusion and including an invalid block then 100% of the stake will be slashed.What’s really important to understand is that both the validators own stake and the nominated stake will be slashed, so you could lose all your DOT that you have staked against a validator if they perform maliciously. Therefore, it’s very important not to just try and maximise rewards and being oblivious to the risk, not only can you lose all your DOT, but you are making the entire system less secure (addressed in part three). There have already been several minor slashing incidents so far, so something to really consider.
https://preview.redd.it/aj9v0azke6m51.png?width=700&format=png&auto=webp&s=86134eaef08d1ef50466d1d80ec5ce151327d702

Auction for Parachain Slots

Due to the limited number of parachain slots available, there needs to be a method to decide who gets a parachain slot. This is achieved through a candle-auction where participants bid with DOT to secure a lease on a parchain slot to secure a 6 — 24 month period, with the highest bidders winning. DOT isn’t spent, but rather locked for the duration of the lease and unable to participate in staking and earn rewards. In the event they are unsuccessful in securing a further slot, then the lease expires and the DOT will be returned.
Of the 100 parachain slots that they hope to be able to accommodate, between 10 and 30 will be reserved for system parachains, with the remaining available for either auction slots or used for parathreads. Whilst the DOT is returned, due to the limited number of slots available this could result in significant amounts of DOT needing to be acquired to secure a slot. How the auction mechanics effect the price of DOT also remains to be seen, with potentially a rise from the start of the auction, followed by a fall before the lease ends and the DOT are returned. The plan is to continuously have a small amount of parachain auctions going throughout the year, to minimise any unwanted effects. How comfortable developers will be with locking significant amounts of funds in a highly volatile asset for an extended amount of time, also remains to be seen. They could also be in a position where they can no longer afford to keep their lease and have to downgrade to a parathread (providing the application will still function with the reduced performance or migrate to another platform). See this article for more details on the auction mechanism
https://preview.redd.it/wp8rvxlme6m51.png?width=387&format=png&auto=webp&s=496320d627405362142210e1a4c17ebe43e1f8a1

Parathreads

For applications that don’t require the guaranteed performance of a parachain or don’t want to pay the large fees to secure a parachain slot, then parathreads can be used instead. Parathreads have a fixed fee for registration that would realistically be much lower than the cost of acquiring a parachain slot and compete with other parathreads in a per-block auction to have their transactions included in the next relay chain block. A portion of the parachain slots on the Relay Chain will be designated as part of the parathread pool.
In the event that a parachain loses its slot then it can transition to a parathread (assuming the application can still function with the reduced and varied performance of sharing the slot between many). This also enables small projects to start out with a parathread and then upgrade to a parachain slot when required.

Token

DOT is the native token of the Polkadot network and serves three key functions. (i) It is staked to provide security for the relay chain, (ii) to be bonded to connect a chain to Polkadot as a parachain and (iii) to be used for governance of the network. There is an initial total supply of 1 billion DOT with yearly inflation estimated to be around 10% providing the optimal 50% staking rate is achieved, resulting in rewards of 20% to those that stake (net 10% when take into account inflation). Those that don’t stake lose 10% through dilution. Should the amount staked exceed the optimal 50% then reward rates reduce as well as inflation to make staking less attractive. Likewise if its below 50% then rewards and inflation rate will be higher to encourage staking. Staking isn’t risk free though as mentioned before.

Governance

Polkadot employs an on-chain governance model where in order to make any changes to the network, DOT holders vote on a proposal to upgrade the network with the help of the Council. The council is an entity comprising a 23 seats each represented by an on-chain account. Its goals are to represent passive stakeholders, submit sensible and important proposals, and cancel dangerous or malicious proposals. All DOT holders are free to register their candidacy for the Council, and free to vote for any number of candidates, with a voting power proportional to their stake.
Any stakeholder can submit a public proposal by depositing a fixed minimum amount of DOTs, which stays locked for a certain period. If someone agrees with the proposal, they may deposit the same amount of tokens to endorse it. Public proposals are stored in a priority queue, and at regular intervals the proposal with the most endorsements gets tabled for a referendum. The locked tokens are released once the proposal is tabled. Council proposals are submitted by the Council, and are stored in a separate priority queue where the priorities are set at the Council’s discretion.
Every thirty days, a new proposal will be tabled, and a referendum will come up for a vote. The proposal to be tabled is the top proposal from either the public-proposal queue or the Council-proposal queue, alternating between the two queues.
The Technical Committee is composed according to a single vote for each team that has successfully and independently implemented or formally specified the protocol in Polkadot, or in its canary network Kusama. The Technical Committee is the last line of defence for the system. Its sole purpose is detecting present or imminent issues in the system such as bugs in the code or security vulnerabilities, and proposing and fast-tracking emergency referenda.

Ecosystem

Whilst parachains aren’t currently implemented at this stage, there is a rapidly growing ecosystem looking to build on Polkadot with substrate. Polkadot’s “cousin”, the canary network Kusama used for experimentation, was launched last year by the same team and contributes to the early growth of the overall ecosystem. See here for a list of the current projects looking to build on Polkadot and filter by Substrate based.
https://preview.redd.it/rt8i0hqpe6m51.png?width=700&format=png&auto=webp&s=f6bcf26fa84463765f720c3074ee10157c2735f6
Now that we have covered the basics, in part two I will explain how the consensus mechanism in Polkadot works and covering more of the technical aspects.
submitted by xSeq22x to CryptoCurrency [link] [comments]

[ CryptoCurrency ] Comparison between Avalanche, Cosmos and Polkadot

[ 🔴 DELETED 🔴 ] Topic originally posted in CryptoCurrency by xSeq22x [link]
A frequent question I see being asked is how Cosmos, Polkadot and Avalanche compare? Whilst there are similarities there are also a lot of differences. This article is not intended to be an extensive in-depth list, but rather an overview based on some of the criteria that I feel are most important.
For better formatting see https://medium.com/ava-hub/comparison-between-avalanche-cosmos-and-polkadot-a2a98f46c03b
https://preview.redd.it/lg16iwk2dhq51.png?width=428&format=png&auto=webp&s=6c899ee69800dd6c5e2900d8fa83de7a43c57086

Overview

Cosmos

Cosmos is a heterogeneous network of many independent parallel blockchains, each powered by classical BFT consensus algorithms like Tendermint. Developers can easily build custom application specific blockchains, called Zones, through the Cosmos SDK framework. These Zones connect to Hubs, which are specifically designed to connect zones together.
The vision of Cosmos is to have thousands of Zones and Hubs that are Interoperable through the Inter-Blockchain Communication Protocol (IBC). Cosmos can also connect to other systems through peg zones, which are specifically designed zones that each are custom made to interact with another ecosystem such as Ethereum and Bitcoin. Cosmos does not use Sharding with each Zone and Hub being sovereign with their own validator set.
For a more in-depth look at Cosmos and provide more reference to points made in this article, please see my three part series — Part One, Part Two, Part Three
https://youtu.be/Eb8xkDi_PUg

Polkadot

Polkadot is a heterogeneous blockchain protocol that connects multiple specialised blockchains into one unified network. It achieves scalability through a sharding infrastructure with multiple blockchains running in parallel, called parachains, that connect to a central chain called the Relay Chain. Developers can easily build custom application specific parachains through the Substrate development framework.
The relay chain validates the state transition of connected parachains, providing shared state across the entire ecosystem. If the Relay Chain must revert for any reason, then all of the parachains would also revert. This is to ensure that the validity of the entire system can persist, and no individual part is corruptible. The shared state makes it so that the trust assumptions when using parachains are only those of the Relay Chain validator set, and no other. Interoperability is enabled between parachains through Cross-Chain Message Passing (XCMP) protocol and is also possible to connect to other systems through bridges, which are specifically designed parachains or parathreads that each are custom made to interact with another ecosystem such as Ethereum and Bitcoin. The hope is to have 100 parachains connect to the relay chain.
For a more in-depth look at Polkadot and provide more reference to points made in this article, please see my three part series — Part One, Part Two, Part Three
https://youtu.be/_-k0xkooSlA

Avalanche

Avalanche is a platform of platforms, ultimately consisting of thousands of subnets to form a heterogeneous interoperable network of many blockchains, that takes advantage of the revolutionary Avalanche Consensus protocols to provide a secure, globally distributed, interoperable and trustless framework offering unprecedented decentralisation whilst being able to comply with regulatory requirements.
Avalanche allows anyone to create their own tailor-made application specific blockchains, supporting multiple custom virtual machines such as EVM and WASM and written in popular languages like Go (with others coming in the future) rather than lightly used, poorly-understood languages like Solidity. This virtual machine can then be deployed on a custom blockchain network, called a subnet, which consist of a dynamic set of validators working together to achieve consensus on the state of a set of many blockchains where complex rulesets can be configured to meet regulatory compliance.
Avalanche was built with serving financial markets in mind. It has native support for easily creating and trading digital smart assets with complex custom rule sets that define how the asset is handled and traded to ensure regulatory compliance can be met. Interoperability is enabled between blockchains within a subnet as well as between subnets. Like Cosmos and Polkadot, Avalanche is also able to connect to other systems through bridges, through custom virtual machines made to interact with another ecosystem such as Ethereum and Bitcoin.
For a more in-depth look at Avalanche and provide more reference to points made in this article, please see here and here
https://youtu.be/mWBzFmzzBAg

Comparison between Cosmos, Polkadot and Avalanche

A frequent question I see being asked is how Cosmos, Polkadot and Avalanche compare? Whilst there are similarities there are also a lot of differences. This article is not intended to be an extensive in-depth list, but rather an overview based on some of the criteria that I feel are most important. For a more in-depth view I recommend reading the articles for each of the projects linked above and coming to your own conclusions. I want to stress that it’s not a case of one platform being the killer of all other platforms, far from it. There won’t be one platform to rule them all, and too often the tribalism has plagued this space. Blockchains are going to completely revolutionise most industries and have a profound effect on the world we know today. It’s still very early in this space with most adoption limited to speculation and trading mainly due to the limitations of Blockchain and current iteration of Ethereum, which all three of these platforms hope to address. For those who just want a quick summary see the image at the bottom of the article. With that said let’s have a look

Scalability

Cosmos

Each Zone and Hub in Cosmos is capable of up to around 1000 transactions per second with bandwidth being the bottleneck in consensus. Cosmos aims to have thousands of Zones and Hubs all connected through IBC. There is no limit on the number of Zones / Hubs that can be created

Polkadot

Parachains in Polkadot are also capable of up to around 1500 transactions per second. A portion of the parachain slots on the Relay Chain will be designated as part of the parathread pool, the performance of a parachain is split between many parathreads offering lower performance and compete amongst themselves in a per-block auction to have their transactions included in the next relay chain block. The number of parachains is limited by the number of validators on the relay chain, they hope to be able to achieve 100 parachains.

Avalanche

Avalanche is capable of around 4500 transactions per second per subnet, this is based on modest hardware requirements to ensure maximum decentralisation of just 2 CPU cores and 4 GB of Memory and with a validator size of over 2,000 nodes. Performance is CPU-bound and if higher performance is required then more specialised subnets can be created with higher minimum requirements to be able to achieve 10,000 tps+ in a subnet. Avalanche aims to have thousands of subnets (each with multiple virtual machines / blockchains) all interoperable with each other. There is no limit on the number of Subnets that can be created.

Results

All three platforms offer vastly superior performance to the likes of Bitcoin and Ethereum 1.0. Avalanche with its higher transactions per second, no limit on the number of subnets / blockchains that can be created and the consensus can scale to potentially millions of validators all participating in consensus scores ✅✅✅. Polkadot claims to offer more tps than cosmos, but is limited to the number of parachains (around 100) whereas with Cosmos there is no limit on the number of hubs / zones that can be created. Cosmos is limited to a fairly small validator size of around 200 before performance degrades whereas Polkadot hopes to be able to reach 1000 validators in the relay chain (albeit only a small number of validators are assigned to each parachain). Thus Cosmos and Polkadot scores ✅✅
https://preview.redd.it/ththwq5qdhq51.png?width=1000&format=png&auto=webp&s=92f75152c90d984911db88ed174ebf3a147ca70d

Decentralisation

Cosmos

Tendermint consensus is limited to around 200 validators before performance starts to degrade. Whilst there is the Cosmos Hub it is one of many hubs in the network and there is no central hub or limit on the number of zones / hubs that can be created.

Polkadot

Polkadot has 1000 validators in the relay chain and these are split up into a small number that validate each parachain (minimum of 14). The relay chain is a central point of failure as all parachains connect to it and the number of parachains is limited depending on the number of validators (they hope to achieve 100 parachains). Due to the limited number of parachain slots available, significant sums of DOT will need to be purchased to win an auction to lease the slot for up to 24 months at a time. Thus likely to lead to only those with enough funds to secure a parachain slot. Parathreads are however an alternative for those that require less and more varied performance for those that can’t secure a parachain slot.

Avalanche

Avalanche consensus scan scale to tens of thousands of validators, even potentially millions of validators all participating in consensus through repeated sub-sampling. The more validators, the faster the network becomes as the load is split between them. There are modest hardware requirements so anyone can run a node and there is no limit on the number of subnets / virtual machines that can be created.

Results

Avalanche offers unparalleled decentralisation using its revolutionary consensus protocols that can scale to millions of validators all participating in consensus at the same time. There is no limit to the number of subnets and virtual machines that can be created, and they can be created by anyone for a small fee, it scores ✅✅✅. Cosmos is limited to 200 validators but no limit on the number of zones / hubs that can be created, which anyone can create and scores ✅✅. Polkadot hopes to accommodate 1000 validators in the relay chain (albeit these are split amongst each of the parachains). The number of parachains is limited and maybe cost prohibitive for many and the relay chain is a ultimately a single point of failure. Whilst definitely not saying it’s centralised and it is more decentralised than many others, just in comparison between the three, it scores ✅
https://preview.redd.it/lv2h7g9sdhq51.png?width=1000&format=png&auto=webp&s=56eada6e8c72dbb4406d7c5377ad15608bcc730e

Latency

Cosmos

Tendermint consensus used in Cosmos reaches finality within 6 seconds. Cosmos consists of many Zones and Hubs that connect to each other. Communication between 2 zones could pass through many hubs along the way, thus also can contribute to latency times depending on the path taken as explained in part two of the articles on Cosmos. It doesn’t need to wait for an extended period of time with risk of rollbacks.

Polkadot

Polkadot provides a Hybrid consensus protocol consisting of Block producing protocol, BABE, and then a finality gadget called GRANDPA that works to agree on a chain, out of many possible forks, by following some simpler fork choice rule. Rather than voting on every block, instead it reaches agreements on chains. As soon as more than 2/3 of validators attest to a chain containing a certain block, all blocks leading up to that one are finalized at once.
If an invalid block is detected after it has been finalised then the relay chain would need to be reverted along with every parachain. This is particularly important when connecting to external blockchains as those don’t share the state of the relay chain and thus can’t be rolled back. The longer the time period, the more secure the network is, as there is more time for additional checks to be performed and reported but at the expense of finality. Finality is reached within 60 seconds between parachains but for external ecosystems like Ethereum their state obviously can’t be rolled back like a parachain and so finality will need to be much longer (60 minutes was suggested in the whitepaper) and discussed in more detail in part three

Avalanche

Avalanche consensus achieves finality within 3 seconds, with most happening sub 1 second, immutable and completely irreversible. Any subnet can connect directly to another without having to go through multiple hops and any VM can talk to another VM within the same subnet as well as external subnets. It doesn’t need to wait for an extended period of time with risk of rollbacks.

Results

With regards to performance far too much emphasis is just put on tps as a metric, the other equally important metric, if not more important with regards to finance is latency. Throughput measures the amount of data at any given time that it can handle whereas latency is the amount of time it takes to perform an action. It’s pointless saying you can process more transactions per second than VISA when it takes 60 seconds for a transaction to complete. Low latency also greatly increases general usability and customer satisfaction, nowadays everyone expects card payments, online payments to happen instantly. Avalanche achieves the best results scoring ✅✅✅, Cosmos with comes in second with 6 second finality ✅✅ and Polkadot with 60 second finality (which may be 60 minutes for external blockchains) scores ✅
https://preview.redd.it/qe8e5ltudhq51.png?width=1000&format=png&auto=webp&s=18a2866104590f81a818690337f9121161dda890

Shared Security

Cosmos

Every Zone and Hub in Cosmos has their own validator set and different trust assumptions. Cosmos are researching a shared security model where a Hub can validate the state of connected zones for a fee but not released yet. Once available this will make shared security optional rather than mandatory.

Polkadot

Shared Security is mandatory with Polkadot which uses a Shared State infrastructure between the Relay Chain and all of the connected parachains. If the Relay Chain must revert for any reason, then all of the parachains would also revert. Every parachain makes the same trust assumptions, and as such the relay chain validates state transition and enables seamless interoperability between them. In return for this benefit, they have to purchase DOT and win an auction for one of the available parachain slots.
However, parachains can’t just rely on the relay chain for their security, they will also need to implement censorship resistance measures and utilise proof of work / proof of stake for each parachain as well as discussed in part three, thus parachains can’t just rely on the security of the relay chain, they need to ensure sybil resistance mechanisms using POW and POS are implemented on the parachain as well.

Avalanche

A subnet in Avalanche consists of a dynamic set of validators working together to achieve consensus on the state of a set of many blockchains where complex rulesets can be configured to meet regulatory compliance. So unlike in Cosmos where each zone / hub has their own validators, A subnet can validate a single or many virtual machines / blockchains with a single validator set. Shared security is optional

Results

Shared security is mandatory in polkadot and a key design decision in its infrastructure. The relay chain validates the state transition of all connected parachains and thus scores ✅✅✅. Subnets in Avalanche can validate state of either a single or many virtual machines. Each subnet can have their own token and shares a validator set, where complex rulesets can be configured to meet regulatory compliance. It scores ✅ ✅. Every Zone and Hub in cosmos has their own validator set / token but research is underway to have the hub validate the state transition of connected zones, but as this is still early in the research phase scores ✅ for now.
https://preview.redd.it/0mnvpnzwdhq51.png?width=1000&format=png&auto=webp&s=8927ff2821415817265be75c59261f83851a2791

Current Adoption

Cosmos

The Cosmos project started in 2016 with an ICO held in April 2017. There are currently around 50 projects building on the Cosmos SDK with a full list can be seen here and filtering for Cosmos SDK . Not all of the projects will necessarily connect using native cosmos sdk and IBC and some have forked parts of the Cosmos SDK and utilise the tendermint consensus such as Binance Chain but have said they will connect in the future.

Polkadot

The Polkadot project started in 2016 with an ICO held in October 2017. There are currently around 70 projects building on Substrate and a full list can be seen here and filtering for Substrate Based. Like with Cosmos not all projects built using substrate will necessarily connect to Polkadot and parachains or parathreads aren’t currently implemented in either the Live or Test network (Kusama) as of the time of this writing.

Avalanche

Avalanche in comparison started much later with Ava Labs being founded in 2018. Avalanche held it’s ICO in July 2020. Due to lot shorter time it has been in development, the number of projects confirmed are smaller with around 14 projects currently building on Avalanche. Due to the customisability of the platform though, many virtual machines can be used within a subnet making the process incredibly easy to port projects over. As an example, it will launch with the Ethereum Virtual Machine which enables byte for byte compatibility and all the tooling like Metamask, Truffle etc. will work, so projects can easily move over to benefit from the performance, decentralisation and low gas fees offered. In the future Cosmos and Substrate virtual machines could be implemented on Avalanche.

Results

Whilst it’s still early for all 3 projects (and the entire blockchain space as a whole), there is currently more projects confirmed to be building on Cosmos and Polkadot, mostly due to their longer time in development. Whilst Cosmos has fewer projects, zones are implemented compared to Polkadot which doesn’t currently have parachains. IBC to connect zones and hubs together is due to launch Q2 2021, thus both score ✅✅✅. Avalanche has been in development for a lot shorter time period, but is launching with an impressive feature set right from the start with ability to create subnets, VMs, assets, NFTs, permissioned and permissionless blockchains, cross chain atomic swaps within a subnet, smart contracts, bridge to Ethereum etc. Applications can easily port over from other platforms and use all the existing tooling such as Metamask / Truffle etc but benefit from the performance, decentralisation and low gas fees offered. Currently though just based on the number of projects in comparison it scores ✅.
https://preview.redd.it/rsctxi6zdhq51.png?width=1000&format=png&auto=webp&s=ff762dea3cfc2aaaa3c8fc7b1070d5be6759aac2

Enterprise Adoption

Cosmos

Cosmos enables permissioned and permissionless zones which can connect to each other with the ability to have full control over who validates the blockchain. For permissionless zones each zone / hub can have their own token and they are in control who validates.

Polkadot

With polkadot the state transition is performed by a small randomly selected assigned group of validators from the relay chain plus with the possibility that state is rolled back if an invalid transaction of any of the other parachains is found. This may pose a problem for enterprises that need complete control over who performs validation for regulatory reasons. In addition due to the limited number of parachain slots available Enterprises would have to acquire and lock up large amounts of a highly volatile asset (DOT) and have the possibility that they are outbid in future auctions and find they no longer can have their parachain validated and parathreads don’t provide the guaranteed performance requirements for the application to function.

Avalanche

Avalanche enables permissioned and permissionless subnets and complex rulesets can be configured to meet regulatory compliance. For example a subnet can be created where its mandatory that all validators are from a certain legal jurisdiction, or they hold a specific license and regulated by the SEC etc. Subnets are also able to scale to tens of thousands of validators, and even potentially millions of nodes, all participating in consensus so every enterprise can run their own node rather than only a small amount. Enterprises don’t have to hold large amounts of a highly volatile asset, but instead pay a fee in AVAX for the creation of the subnets and blockchains which is burnt.

Results

Avalanche provides the customisability to run private permissioned blockchains as well as permissionless where the enterprise is in control over who validates the blockchain, with the ability to use complex rulesets to meet regulatory compliance, thus scores ✅✅✅. Cosmos is also able to run permissioned and permissionless zones / hubs so enterprises have full control over who validates a blockchain and scores ✅✅. Polkadot requires locking up large amounts of a highly volatile asset with the possibility of being outbid by competitors and being unable to run the application if the guaranteed performance is required and having to migrate away. The relay chain validates the state transition and can roll back the parachain should an invalid block be detected on another parachain, thus scores ✅.
https://preview.redd.it/7phaylb1ehq51.png?width=1000&format=png&auto=webp&s=d86d2ec49de456403edbaf27009ed0e25609fbff

Interoperability

Cosmos

Cosmos will connect Hubs and Zones together through its IBC protocol (due to release in Q1 2020). Connecting to blockchains outside of the Cosmos ecosystem would either require the connected blockchain to fork their code to implement IBC or more likely a custom “Peg Zone” will be created specific to work with a particular blockchain it’s trying to bridge to such as Ethereum etc. Each Zone and Hub has different trust levels and connectivity between 2 zones can have different trust depending on which path it takes (this is discussed more in this article). Finality time is low at 6 seconds, but depending on the number of hops, this can increase significantly.

Polkadot

Polkadot’s shared state means each parachain that connects shares the same trust assumptions, of the relay chain validators and that if one blockchain needs to be reverted, all of them will need to be reverted. Interoperability is enabled between parachains through Cross-Chain Message Passing (XCMP) protocol and is also possible to connect to other systems through bridges, which are specifically designed parachains or parathreads that each are custom made to interact with another ecosystem such as Ethereum and Bitcoin. Finality time between parachains is around 60 seconds, but longer will be needed (initial figures of 60 minutes in the whitepaper) for connecting to external blockchains. Thus limiting the appeal of connecting two external ecosystems together through Polkadot. Polkadot is also limited in the number of Parachain slots available, thus limiting the amount of blockchains that can be bridged. Parathreads could be used for lower performance bridges, but the speed of future blockchains is only going to increase.

Avalanche

A subnet can validate multiple virtual machines / blockchains and all blockchains within a subnet share the same trust assumptions / validator set, enabling cross chain interoperability. Interoperability is also possible between any other subnet, with the hope Avalanche will consist of thousands of subnets. Each subnet may have a different trust level, but as the primary network consists of all validators then this can be used as a source of trust if required. As Avalanche supports many virtual machines, bridges to other ecosystems are created by running the connected virtual machine. There will be an Ethereum bridge using the EVM shortly after mainnet. Finality time is much faster at sub 3 seconds (with most happening under 1 second) with no chance of rolling back so more appealing when connecting to external blockchains.

Results

All 3 systems are able to perform interoperability within their ecosystem and transfer assets as well as data, as well as use bridges to connect to external blockchains. Cosmos has different trust levels between its zones and hubs and can create issues depending on which path it takes and additional latency added. Polkadot provides the same trust assumptions for all connected parachains but has long finality and limited number of parachain slots available. Avalanche provides the same trust assumptions for all blockchains within a subnet, and different trust levels between subnets. However due to the primary network consisting of all validators it can be used for trust. Avalanche also has a much faster finality time with no limitation on the number of blockchains / subnets / bridges that can be created. Overall all three blockchains excel with interoperability within their ecosystem and each score ✅✅.
https://preview.redd.it/l775gue3ehq51.png?width=1000&format=png&auto=webp&s=b7c4b5802ceb1a9307bd2a8d65f393d1bcb0d7c6

Tokenomics

Cosmos

The ATOM token is the native token for the Cosmos Hub. It is commonly mistaken by people that think it’s the token used throughout the cosmos ecosystem, whereas it’s just used for one of many hubs in Cosmos, each with their own token. Currently ATOM has little utility as IBC isn’t released and has no connections to other zones / hubs. Once IBC is released zones may prefer to connect to a different hub instead and so ATOM is not used. ATOM isn’t a fixed capped supply token and supply will continuously increase with a yearly inflation of around 10% depending on the % staked. The current market cap for ATOM as of the time of this writing is $1 Billion with 203 million circulating supply. Rewards can be earnt through staking to offset the dilution caused by inflation. Delegators can also get slashed and lose a portion of their ATOM should the validator misbehave.

Polkadot

Polkadot’s native token is DOT and it’s used to secure the Relay Chain. Each parachain needs to acquire sufficient DOT to win an auction on an available parachain lease period of up to 24 months at a time. Parathreads have a fixed fee for registration that would realistically be much lower than the cost of acquiring a parachain slot and compete with other parathreads in a per-block auction to have their transactions included in the next relay chain block. DOT isn’t a fixed capped supply token and supply will continuously increase with a yearly inflation of around 10% depending on the % staked. The current market cap for DOT as of the time of this writing is $4.4 Billion with 852 million circulating supply. Delegators can also get slashed and lose their DOT (potentially 100% of their DOT for serious attacks) should the validator misbehave.

Avalanche

AVAX is the native token for the primary network in Avalanche. Every validator of any subnet also has to validate the primary network and stake a minimum of 2000 AVAX. There is no limit to the number of validators like other consensus methods then this can cater for tens of thousands even potentially millions of validators. As every validator validates the primary network, this can be a source of trust for interoperability between subnets as well as connecting to other ecosystems, thus increasing amount of transaction fees of AVAX. There is no slashing in Avalanche, so there is no risk to lose your AVAX when selecting a validator, instead rewards earnt for staking can be slashed should the validator misbehave. Because Avalanche doesn’t have direct slashing, it is technically possible for someone to both stake AND deliver tokens for something like a flash loan, under the invariant that all tokens that are staked are returned, thus being able to make profit with staked tokens outside of staking itself.
There will also be a separate subnet for Athereum which is a ‘spoon,’ or friendly fork, of Ethereum, which benefits from the Avalanche consensus protocol and applications in the Ethereum ecosystem. It’s native token ATH will be airdropped to ETH holders as well as potentially AVAX holders as well. This can be done for other blockchains as well.
Transaction fees on the primary network for all 3 of the blockchains as well as subscription fees for creating a subnet and blockchain are paid in AVAX and are burnt, creating deflationary pressure. AVAX is a fixed capped supply of 720 million tokens, creating scarcity rather than an unlimited supply which continuously increase of tokens at a compounded rate each year like others. Initially there will be 360 tokens minted at Mainnet with vesting periods between 1 and 10 years, with tokens gradually unlocking each quarter. The Circulating supply is 24.5 million AVAX with tokens gradually released each quater. The current market cap of AVAX is around $100 million.

Results

Avalanche’s AVAX with its fixed capped supply, deflationary pressure, very strong utility, potential to receive air drops and low market cap, means it scores ✅✅✅. Polkadot’s DOT also has very strong utility with the need for auctions to acquire parachain slots, but has no deflationary mechanisms, no fixed capped supply and already valued at $3.8 billion, therefore scores ✅✅. Cosmos’s ATOM token is only for the Cosmos Hub, of which there will be many hubs in the ecosystem and has very little utility currently. (this may improve once IBC is released and if Cosmos hub actually becomes the hub that people want to connect to and not something like Binance instead. There is no fixed capped supply and currently valued at $1.1 Billion, so scores ✅.
https://preview.redd.it/zb72eto5ehq51.png?width=1000&format=png&auto=webp&s=0ee102a2881d763296ad9ffba20667f531d2fd7a
All three are excellent projects and have similarities as well as many differences. Just to reiterate this article is not intended to be an extensive in-depth list, but rather an overview based on some of the criteria that I feel are most important. For a more in-depth view I recommend reading the articles for each of the projects linked above and coming to your own conclusions, you may have different criteria which is important to you, and score them differently. There won’t be one platform to rule them all however, with some uses cases better suited to one platform over another, and it’s not a zero-sum game. Blockchain is going to completely revolutionize industries and the Internet itself. The more projects researching and delivering breakthrough technology the better, each learning from each other and pushing each other to reach that goal earlier. The current market is a tiny speck of what’s in store in terms of value and adoption and it’s going to be exciting to watch it unfold.
https://preview.redd.it/fwi3clz7ehq51.png?width=1388&format=png&auto=webp&s=c91c1645a4c67defd5fc3aaec84f4a765e1c50b6
xSeq22x your post has been copied because one or more comments in this topic have been removed. This copy will preserve unmoderated topic. If you would like to opt-out, please send a message using [this link].
submitted by anticensor_bot to u/anticensor_bot [link] [comments]

Scaling Reddit Community Points with Arbitrum Rollup: a piece of cake

Scaling Reddit Community Points with Arbitrum Rollup: a piece of cake
https://preview.redd.it/b80c05tnb9e51.jpg?width=2550&format=pjpg&auto=webp&s=850282c1a3962466ed44f73886dae1c8872d0f31
Submitted for consideration to The Great Reddit Scaling Bake-Off
Baked by the pastry chefs at Offchain Labs
Please send questions or comments to [[email protected] ](mailto:[email protected])
1. Overview
We're excited to submit Arbitrum Rollup for consideration to The Great Reddit Scaling Bake-Off. Arbitrum Rollup is the only Ethereum scaling solution that supports arbitrary smart contracts without compromising on Ethereum's security or adding points of centralization. For Reddit, this means that Arbitrum can not only scale the minting and transfer of Community Points, but it can foster a creative ecosystem built around Reddit Community Points enabling points to be used in a wide variety of third party applications. That's right -- you can have your cake and eat it too!
Arbitrum Rollup isn't just Ethereum-style. Its Layer 2 transactions are byte-for-byte identical to Ethereum, which means Ethereum users can continue to use their existing addresses and wallets, and Ethereum developers can continue to use their favorite toolchains and development environments out-of-the-box with Arbitrum. Coupling Arbitrum’s tooling-compatibility with its trustless asset interoperability, Reddit not only can scale but can onboard the entire Ethereum community at no cost by giving them the same experience they already know and love (well, certainly know).
To benchmark how Arbitrum can scale Reddit Community Points, we launched the Reddit contracts on an Arbitrum Rollup chain. Since Arbitrum provides full Solidity support, we didn't have to rewrite the Reddit contracts or try to mimic their functionality using an unfamiliar paradigm. Nope, none of that. We launched the Reddit contracts unmodified on Arbitrum Rollup complete with support for minting and distributing points. Like every Arbitrum Rollup chain, the chain included a bridge interface in which users can transfer Community Points or any other asset between the L1 and L2 chains. Arbitrum Rollup chains also support dynamic contract loading, which would allow third-party developers to launch custom ecosystem apps that integrate with Community Points on the very same chain that runs the Reddit contracts.
1.1 Why Ethereum
Perhaps the most exciting benefit of distributing Community Points using a blockchain is the ability to seamlessly port points to other applications and use them in a wide variety of contexts. Applications may include simple transfers such as a restaurant that allows Redditors to spend points on drinks. Or it may include complex smart contracts -- such as placing Community Points as a wager for a multiparty game or as collateral in a financial contract.
The common denominator between all of the fun uses of Reddit points is that it needs a thriving ecosystem of both users and developers, and the Ethereum blockchain is perhaps the only smart contract platform with significant adoption today. While many Layer 1 blockchains boast lower cost or higher throughput than the Ethereum blockchain, more often than not, these attributes mask the reality of little usage, weaker security, or both.
Perhaps another platform with significant usage will rise in the future. But today, Ethereum captures the mindshare of the blockchain community, and for Community Points to provide the most utility, the Ethereum blockchain is the natural choice.
1.2 Why Arbitrum
While Ethereum's ecosystem is unmatched, the reality is that fees are high and capacity is too low to support the scale of Reddit Community Points. Enter Arbitrum. Arbitrum Rollup provides all of the ecosystem benefits of Ethereum, but with orders of magnitude more capacity and at a fraction of the cost of native Ethereum smart contracts. And most of all, we don't change the experience from users. They continue to use the same wallets, addresses, languages, and tools.
Arbitrum Rollup is not the only solution that can scale payments, but it is the only developed solution that can scale both payments and arbitrary smart contracts trustlessly, which means that third party users can build highly scalable add-on apps that can be used without withdrawing money from the Rollup chain. If you believe that Reddit users will want to use their Community Points in smart contracts--and we believe they will--then it makes the most sense to choose a single scaling solution that can support the entire ecosystem, eliminating friction for users.
We view being able to run smart contracts in the same scaling solution as fundamentally critical since if there's significant demand in running smart contracts from Reddit's ecosystem, this would be a load on Ethereum and would itself require a scaling solution. Moreover, having different scaling solutions for the minting/distribution/spending of points and for third party apps would be burdensome for users as they'd have to constantly shuffle their Points back and forth.
2. Arbitrum at a glance
Arbitrum Rollup has a unique value proposition as it offers a combination of features that no other scaling solution achieves. Here we highlight its core attributes.
Decentralized. Arbitrum Rollup is as decentralized as Ethereum. Unlike some other Layer 2 scaling projects, Arbitrum Rollup doesn't have any centralized components or centralized operators who can censor users or delay transactions. Even in non-custodial systems, centralized components provide a risk as the operators are generally incentivized to increase their profit by extracting rent from users often in ways that severely degrade user experience. Even if centralized operators are altruistic, centralized components are subject to hacking, coercion, and potential liability.
Massive Scaling. Arbitrum achieves order of magnitude scaling over Ethereum's L1 smart contracts. Our software currently supports 453 transactions-per-second for basic transactions (at 1616 Ethereum gas per tx). We have a lot of room left to optimize (e.g. aggregating signatures), and over the next several months capacity will increase significantly. As described in detail below, Arbitrum can easily support and surpass Reddit's anticipated initial load, and its capacity will continue to improve as Reddit's capacity needs grow.
Low cost. The cost of running Arbitrum Rollup is quite low compared to L1 Ethereum and other scaling solutions such as those based on zero-knowledge proofs. Layer 2 fees are low, fixed, and predictable and should not be overly burdensome for Reddit to cover. Nobody needs to use special equipment or high-end machines. Arbitrum requires validators, which is a permissionless role that can be run on any reasonable on-line machine. Although anybody can act as a validator, in order to protect against a “tragedy of the commons” and make sure reputable validators are participating, we support a notion of “invited validators” that are compensated for their costs. In general, users pay (low) fees to cover the invited validators’ costs, but we imagine that Reddit may cover this cost for its users. See more on the costs and validator options below.
Ethereum Developer Experience. Not only does Arbitrum support EVM smart contracts, but the developer experience is identical to that of L1 Ethereum contracts and fully compatible with Ethereum tooling. Developers can port existing Solidity apps or write new ones using their favorite and familiar toolchains (e.g. Truffle, Buidler). There are no new languages or coding paradigms to learn.
Ethereum wallet compatibility. Just as in Ethereum, Arbitrum users need only hold keys, but do not have to store any coin history or additional data to protect or access their funds. Since Arbitrum transactions are semantically identical to Ethereum L1 transactions, existing Ethereum users can use their existing Ethereum keys with their existing wallet software such as Metamask.
Token interoperability. Users can easily transfer their ETH, ERC-20 and ERC-721 tokens between Ethereum and the Arbitrum Rollup chain. As we explain in detail below, it is possible to mint tokens in L2 that can subsequently be withdrawn and recognized by the L1 token contract.
Fast finality. Transactions complete with the same finality time as Ethereum L1 (and it's possible to get faster finality guarantees by trading away trust assumptions; see the Arbitrum Rollup whitepaper for details).
Non-custodial. Arbitrum Rollup is a non-custodial scaling solution, so users control their funds/points and neither Reddit nor anyone else can ever access or revoke points held by users.
Censorship Resistant. Since it's completely decentralized, and the Arbitrum protocol guarantees progress trustlessly, Arbitrum Rollup is just as censorship-proof as Ethereum.
Block explorer. The Arbitrum Rollup block explorer allows users to view and analyze transactions on the Rollup chain.
Limitations
Although this is a bake-off, we're not going to sugar coat anything. Arbitrum Rollup, like any Optimistic Rollup protocol, does have one limitation, and that's the delay on withdrawals.
As for the concrete length of the delay, we've done a good deal of internal modeling and have blogged about this as well. Our current modeling suggests a 3-hour delay is sufficient (but as discussed in the linked post there is a tradeoff space between the length of the challenge period and the size of the validators’ deposit).
Note that this doesn't mean that the chain is delayed for three hours. Arbitrum Rollup supports pipelining of execution, which means that validators can keep building new states even while previous ones are “in the pipeline” for confirmation. As the challenge delays expire for each update, a new state will be confirmed (read more about this here).
So activity and progress on the chain are not delayed by the challenge period. The only thing that's delayed is the consummation of withdrawals. Recall though that any single honest validator knows immediately (at the speed of L1 finality) which state updates are correct and can guarantee that they will eventually be confirmed, so once a valid withdrawal has been requested on-chain, every honest party knows that the withdrawal will definitely happen. There's a natural place here for a liquidity market in which a validator (or someone who trusts a validator) can provide withdrawal loans for a small interest fee. This is a no-risk business for them as they know which withdrawals will be confirmed (and can force their confirmation trustlessly no matter what anyone else does) but are just waiting for on-chain finality.
3. The recipe: How Arbitrum Rollup works
For a description of the technical components of Arbitrum Rollup and how they interact to create a highly scalable protocol with a developer experience that is identical to Ethereum, please refer to the following documents:
Arbitrum Rollup Whitepaper
Arbitrum academic paper (describes a previous version of Arbitrum)
4. Developer docs and APIs
For full details about how to set up and interact with an Arbitrum Rollup chain or validator, please refer to our developer docs, which can be found at https://developer.offchainlabs.com/.
Note that the Arbitrum version described on that site is older and will soon be replaced by the version we are entering in Reddit Bake-Off, which is still undergoing internal testing before public release.
5. Who are the validators?
As with any Layer 2 protocol, advancing the protocol correctly requires at least one validator (sometimes called block producers) that is honest and available. A natural question is: who are the validators?
Recall that the validator set for an Arbitrum chain is open and permissionless; anyone can start or stop validating at will. (A useful analogy is to full nodes on an L1 chain.) But we understand that even though anyone can participate, Reddit may want to guarantee that highly reputable nodes are validating their chain. Reddit may choose to validate the chain themselves and/or hire third-party validators.To this end, we have begun building a marketplace for validator-for-hire services so that dapp developers can outsource validation services to reputable nodes with high up-time. We've announced a partnership in which Chainlink nodes will provide Arbitrum validation services, and we expect to announce more partnerships shortly with other blockchain infrastructure providers.
Although there is no requirement that validators are paid, Arbitrum’s economic model tracks validators’ costs (e.g. amount of computation and storage) and can charge small fees on user transactions, using a gas-type system, to cover those costs. Alternatively, a single party such as Reddit can agree to cover the costs of invited validators.
6. Reddit Contract Support
Since Arbitrum contracts and transactions are byte-for-byte compatible with Ethereum, supporting the Reddit contracts is as simple as launching them on an Arbitrum chain.
Minting. Arbitrum Rollup supports hybrid L1/L2 tokens which can be minted in L2 and then withdrawn onto the L1. An L1 contract at address A can make a special call to the EthBridge which deploys a "buddy contract" to the same address A on an Arbitrum chain. Since it's deployed at the same address, users can know that the L2 contract is the authorized "buddy" of the L1 contract on the Arbitrum chain.
For minting, the L1 contract is a standard ERC-20 contract which mints and burns tokens when requested by the L2 contract. It is paired with an ERC-20 contract in L2 which mints tokens based on whatever programmer provided minting facility is desired and burns tokens when they are withdrawn from the rollup chain. Given this base infrastructure, Arbitrum can support any smart contract based method for minting tokens in L2, and indeed we directly support Reddit's signature/claim based minting in L2.
Batch minting. What's better than a mint cookie? A whole batch! In addition to supporting Reddit’s current minting/claiming scheme, we built a second minting design, which we believe outperforms the signature/claim system in many scenarios.
In the current system, Reddit periodically issues signed statements to users, who then take those statements to the blockchain to claim their tokens. An alternative approach would have Reddit directly submit the list of users/amounts to the blockchain and distribute the tokens to the users without the signature/claim process.
To optimize the cost efficiency of this approach, we designed an application-specific compression scheme to minimize the size of the batch distribution list. We analyzed the data from Reddit's previous distributions and found that the data is highly compressible since token amounts are small and repeated, and addresses appear multiple times. Our function groups transactions by size, and replaces previously-seen addresses with a shorter index value. We wrote client code to compress the data, wrote a Solidity decompressing function, and integrated that function into Reddit’s contract running on Arbitrum.
When we ran the compression function on the previous Reddit distribution data, we found that we could compress batched minting data down to to 11.8 bytes per minting event (averaged over a 6-month trace of Reddit’s historical token grants)compared with roughly 174 bytes of on-chain data needed for the signature claim approach to minting (roughly 43 for an RLP-encoded null transaction + 65 for Reddit's signature + 65 for the user's signature + roughly 8 for the number of Points) .
The relative benefit of the two approaches with respect to on-chain call data cost depends on the percentage of users that will actually claim their tokens on chain. With the above figures, batch minting will be cheaper if roughly 5% of users redeem their claims. We stress that our compression scheme is not Arbitrum-specific and would be beneficial in any general-purpose smart contract platform.
8. Benchmarks and costs
In this section, we give the full costs of operating the Reddit contracts on an Arbitrum Rollup chain including the L1 gas costs for the Rollup chain, the costs of computation and storage for the L2 validators as well as the capital lockup requirements for staking.
Arbitrum Rollup is still on testnet, so we did not run mainnet benchmarks. Instead, we measured the L1 gas cost and L2 workload for Reddit operations on Arbitrum and calculated the total cost assuming current Ethereum gas prices. As noted below in detail, our measurements do not assume that Arbitrum is consuming the entire capacity of Ethereum. We will present the details of our model now, but for full transparency you can also play around with it yourself and adjust the parameters, by copying the spreadsheet found here.
Our cost model is based on measurements of Reddit’s contracts, running unmodified (except for the addition of a batch minting function) on Arbitrum Rollup on top of Ethereum.
On the distribution of transactions and frequency of assertions. Reddit's instructions specify the following minimum parameters that submissions should support:
Over a 5 day period, your scaling PoC should be able to handle:
  • 100,000 point claims (minting & distributing points)
  • 25,000 subscriptions
  • 75,000 one-off points burning
  • 100,000 transfers
We provide the full costs of operating an Arbitrum Rollup chain with this usage under the assumption that tokens are minted or granted to users in batches, but other transactions are uniformly distributed over the 5 day period. Unlike some other submissions, we do not make unrealistic assumptions that all operations can be submitted in enormous batches. We assume that batch minting is done in batches that use only a few percent on an L1 block’s gas, and that other operations come in evenly over time and are submitted in batches, with one batch every five minutes to keep latency reasonable. (Users are probably already waiting for L1 finality, which takes at least that long to achieve.)
We note that assuming that there are only 300,000 transactions that arrive uniformly over the 5 day period will make our benchmark numbers lower, but we believe that this will reflect the true cost of running the system. To see why, say that batches are submitted every five minutes (20 L1 blocks) and there's a fixed overhead of c bytes of calldata per batch, the cost of which will get amortized over all transactions executed in that batch. Assume that each individual transaction adds a marginal cost of t. Lastly assume the capacity of the scaling system is high enough that it can support all of Reddit's 300,000 transactions within a single 20-block batch (i.e. that there is more than c + 300,000*t byes of calldata available in 20 blocks).
Consider what happens if c, the per-batch overhead, is large (which it is in some systems, but not in Arbitrum). In the scenario that transactions actually arrive at the system's capacity and each batch is full, then c gets amortized over 300,000 transactions. But if we assume that the system is not running at capacity--and only receives 300,000 transactions arriving uniformly over 5 days-- then each 20-block assertion will contain about 200 transactions, and thus each transaction will pay a nontrivial cost due to c.
We are aware that other proposals presented scaling numbers assuming that 300,000 transactions arrived at maximum capacity and was executed in a single mega-transaction, but according to our estimates, for at least one such report, this led to a reported gas price that was 2-3 orders of magnitude lower than it would have been assuming uniform arrival. We make more realistic batching assumptions, and we believe Arbitrum compares well when batch sizes are realistic.
Our model. Our cost model includes several sources of cost:
  • L1 gas costs: This is the cost of posting transactions as calldata on the L1 chain, as well as the overhead associated with each batch of transactions, and the L1 cost of settling transactions in the Arbitrum protocol.
  • Validator’s staking costs: In normal operation, one validator will need to be staked. The stake is assumed to be 0.2% of the total value of the chain (which is assumed to be $1 per user who is eligible to claim points). The cost of staking is the interest that could be earned on the money if it were not staked.
  • Validator computation and storage: Every validator must do computation to track the chain’s processing of transactions, and must maintain storage to keep track of the contracts’ EVM storage. The cost of computation and storage are estimated based on measurements, with the dollar cost of resources based on Amazon Web Services pricing.
It’s clear from our modeling that the predominant cost is for L1 calldata. This will probably be true for any plausible rollup-based system.
Our model also shows that Arbitrum can scale to workloads much larger than Reddit’s nominal workload, without exhausting L1 or L2 resources. The scaling bottleneck will ultimately be calldata on the L1 chain. We believe that cost could be reduced substantially if necessary by clever encoding of data. (In our design any compression / decompression of L2 transaction calldata would be done by client software and L2 programs, never by an L1 contract.)
9. Status of Arbitrum Rollup
Arbitrum Rollup is live on Ethereum testnet. All of the code written to date including everything included in the Reddit demo is open source and permissively licensed under the Apache V2 license. The first testnet version of Arbitrum Rollup was released on testnet in February. Our current internal version, which we used to benchmark the Reddit contracts, will be released soon and will be a major upgrade.
Both the Arbitrum design as well as the implementation are heavily audited by independent third parties. The Arbitrum academic paper was published at USENIX Security, a top-tier peer-reviewed academic venue. For the Arbitrum software, we have engaged Trail of Bits for a security audit, which is currently ongoing, and we are committed to have a clean report before launching on Ethereum mainnet.
10. Reddit Universe Arbitrum Rollup Chain
The benchmarks described in this document were all measured using the latest internal build of our software. When we release the new software upgrade publicly we will launch a Reddit Universe Arbitrum Rollup chain as a public demo, which will contain the Reddit contracts as well as a Uniswap instance and a Connext Hub, demonstrating how Community Points can be integrated into third party apps. We will also allow members of the public to dynamically launch ecosystem contracts. We at Offchain Labs will cover the validating costs for the Reddit Universe public demo.
If the folks at Reddit would like to evaluate our software prior to our public demo, please email us at [email protected] and we'd be more than happy to provide early access.
11. Even more scaling: Arbitrum Sidechains
Rollups are an excellent approach to scaling, and we are excited about Arbitrum Rollup which far surpasses Reddit's scaling needs. But looking forward to Reddit's eventual goal of supporting hundreds of millions of users, there will likely come a time when Reddit needs more scaling than any Rollup protocol can provide.
While Rollups greatly reduce costs, they don't break the linear barrier. That is, all transactions have an on-chain footprint (because all calldata must be posted on-chain), albeit a far smaller one than on native Ethereum, and the L1 limitations end up being the bottleneck for capacity and cost. Since Ethereum has limited capacity, this linear use of on-chain resources means that costs will eventually increase superlinearly with traffic.
The good news is that we at Offchain Labs have a solution in our roadmap that can satisfy this extreme-scaling setting as well: Arbitrum AnyTrust Sidechains. Arbitrum Sidechains are similar to Arbitrum Rollup, but deviate in that they name a permissioned set of validators. When a chain’s validators agree off-chain, they can greatly reduce the on-chain footprint of the protocol and require almost no data to be put on-chain. When validators can't reach unanimous agreement off-chain, the protocol reverts to Arbitrum Rollup. Technically, Arbitrum Sidechains can be viewed as a hybrid between state channels and Rollup, switching back and forth as necessary, and combining the performance and cost that state channels can achieve in the optimistic case, with the robustness of Rollup in other cases. The core technical challenge is how to switch seamlessly between modes and how to guarantee that security is maintained throughout.
Arbitrum Sidechains break through this linear barrier, while still maintaining a high level of security and decentralization. Arbitrum Sidechains provide the AnyTrust guarantee, which says that as long as any one validator is honest and available (even if you don't know which one will be), the L2 chain is guaranteed to execute correctly according to its code and guaranteed to make progress. Unlike in a state channel, offchain progress does not require unanimous consent, and liveness is preserved as long as there is a single honest validator.
Note that the trust model for Arbitrum Sidechains is much stronger than for typical BFT-style chains which introduce a consensus "voting" protocols among a small permissioned group of validators. BFT-based protocols require a supermajority (more than 2/3) of validators to agree. In Arbitrum Sidechains, by contrast, all you need is a single honest validator to achieve guaranteed correctness and progress. Notice that in Arbitrum adding validators strictly increases security since the AnyTrust guarantee provides correctness as long as any one validator is honest and available. By contrast, in BFT-style protocols, adding nodes can be dangerous as a coalition of dishonest nodes can break the protocol.
Like Arbitrum Rollup, the developer and user experiences for Arbitrum Sidechains will be identical to that of Ethereum. Reddit would be able to choose a large and diverse set of validators, and all that they would need to guarantee to break through the scaling barrier is that a single one of them will remain honest.
We hope to have Arbitrum Sidechains in production in early 2021, and thus when Reddit reaches the scale that surpasses the capacity of Rollups, Arbitrum Sidechains will be waiting and ready to help.
While the idea to switch between channels and Rollup to get the best of both worlds is conceptually simple, getting the details right and making sure that the switch does not introduce any attack vectors is highly non-trivial and has been the subject of years of our research (indeed, we were working on this design for years before the term Rollup was even coined).
12. How Arbitrum compares
We include a comparison to several other categories as well as specific projects when appropriate. and explain why we believe that Arbitrum is best suited for Reddit's purposes. We focus our attention on other Ethereum projects.
Payment only Rollups. Compared to Arbitrum Rollup, ZK-Rollups and other Rollups that only support token transfers have several disadvantages:
  • As outlined throughout the proposal, we believe that the entire draw of Ethereum is in its rich smart contracts support which is simply not achievable with today's zero-knowledge proof technology. Indeed, scaling with a ZK-Rollup will add friction to the deployment of smart contracts that interact with Community Points as users will have to withdraw their coins from the ZK-Rollup and transfer them to a smart contract system (like Arbitrum). The community will be best served if Reddit builds on a platform that has built-in, frictionless smart-contract support.
  • All other Rollup protocols of which we are aware employ a centralized operator. While it's true that users retain custody of their coins, the centralized operator can often profit from censoring, reordering, or delaying transactions. A common misconception is that since they're non-custodial protocols, a centralized sequencer does not pose a risk but this is incorrect as the sequencer can wreak havoc or shake down users for side payments without directly stealing funds.
  • Sidechain type protocols can eliminate some of these issues, but they are not trustless. Instead, they require trust in some quorum of a committee, often requiring two-third of the committee to be honest, compared to rollup protocols like Arbitrum that require only a single honest party. In addition, not all sidechain type protocols have committees that are diverse, or even non-centralized, in practice.
  • Plasma-style protocols have a centralized operator and do not support general smart contracts.
13. Concluding Remarks
While it's ultimately up to the judges’ palate, we believe that Arbitrum Rollup is the bakeoff choice that Reddit kneads. We far surpass Reddit's specified workload requirement at present, have much room to optimize Arbitrum Rollup in the near term, and have a clear path to get Reddit to hundreds of millions of users. Furthermore, we are the only project that gives developers and users the identical interface as the Ethereum blockchain and is fully interoperable and tooling-compatible, and we do this all without any new trust assumptions or centralized components.
But no matter how the cookie crumbles, we're glad to have participated in this bake-off and we thank you for your consideration.
About Offchain Labs
Offchain Labs, Inc. is a venture-funded New York company that spun out of Princeton University research, and is building the Arbitrum platform to usher in the next generation of scalable, interoperable, and compatible smart contracts. Offchain Labs is backed by Pantera Capital, Compound VC, Coinbase Ventures, and others.
Leadership Team
Ed Felten
Ed Felten is Co-founder and Chief Scientist at Offchain Labs. He is on leave from Princeton University, where he is the Robert E. Kahn Professor of Computer Science and Public Affairs. From 2015 to 2017 he served at the White House as Deputy United States Chief Technology Officer and senior advisor to the President. He is an ACM Fellow and member of the National Academy of Engineering. Outside of work, he is an avid runner, cook, and L.A. Dodgers fan.
Steven Goldfeder
Steven Goldfeder is Co-founder and Chief Executive Officer at Offchain Labs. He holds a PhD from Princeton University, where he worked at the intersection of cryptography and cryptocurrencies including threshold cryptography, zero-knowledge proof systems, and post-quantum signatures. He is a co-author of Bitcoin and Cryptocurrency Technologies, the leading textbook on cryptocurrencies, and he has previously worked at Google and Microsoft Research, where he co-invented the Picnic signature algorithm. When not working, you can find Steven spending time with his family, taking a nature walk, or twisting balloons.
Harry Kalodner
Harry Kalodner is Co-founder and Chief Technology Officer at Offchain Labs where he leads the engineering team. Before the company he attended Princeton as a Ph.D candidate where his research explored economics, anonymity, and incentive compatibility of cryptocurrencies, and he also has worked at Apple. When not up at 3:00am writing code, Harry occasionally sleeps.
submitted by hkalodner to ethereum [link] [comments]

My stock study watchlist. would appreciate criticisms or red flags

Core
- FB ecosystem
This is the stock that i believe is invested in the right places and has a path forward in the global market. I work as a React developer in fintech and I greatly enjoy their technology. The reason I stopped using snapchat was because I couldn't use it on low connection in Mexico, but Instagram worked marvelously. I use Whatsapp to stay in touch with my family in mexico and Facebook to stay in touch with my mom. There's something extremely powerful about that in my opinion.
They're conservative with their push and development of camera and VR technology which is wise in my opinion give the many opportunities that exist in that space. They're pushing along with fintech in India, again with small business through Whatsapp. And they provide a suite of customer services for small business and entrepeneurs.

- Microsoft
I think they will have a great run during the cloud era of software development. Their acquiring of Github AND NPM goes to show how in touch they are with developer servicing.

- Paypal
Paypal has a marvelous history and is a battle tested pioneer in the fintech space. I see them repeating their previous successes by acquiring Honey. I work with Honey in the fintech space and now I'm understanding that Paypal has an auto coupon scraper on my Amazon purchases while my Visa ones don't. This is the forward thinking I love from Paypal despite not being as flashy as Square.

- Disney
Disney is quintessential american entertainment. I believe their deep roots in American culture and the entertainment industry will provide a solid bedrock for them for the generations to come.

- Waste Management
Sanitation and environmental, like internet connection technology, are about the same when it comes to market penetration. It is a scarcity. Sanitation is a critical part of any society's development and wellbeing. I think WM will be there to benefit from increased urbanization and industriousness from technology and wealth growth.

- Kansas City Southern
I'm Mexican and my family are avocado farmers. I believe in the future prospects of Mexico and its relationship with its neighbors. Mexico is a bustling nation and many youth are international students that carry degrees. This is a far cry from having military policing streets in rural neighborhoods decades ago. Kansas city southern is part of the supply chain that connects Mexico to main industrious Mexican states like Monterrey, Jalisco, and Michaocan. I like rail in this regard because it's a lot of weight in one operation of heavy materials. So Canadians that use Mexican mining will also benefit from this railroad.
- Nintendo
I believe in the future of gaming as a market and if I were to take a shot at who would be the most stable, I would vote for Nintendo. Like Facebook, they approach the family unit and grow generationally. I love their curveball approach to gaming and I think that creativity, along with it's customers trust, will be something I can hold onto for a long time versus companies that have a history of developing games like Call of Duty or World of Warcraft. Nintendo can take different forms: in the living room, at sweaty tournaments, online, mobile, on your phone, on a TV, in the movies, etc.

Closely watching
- United Health or Cigna
This is only going to grow and wont change due to American politics for 8 years at a minimum.
- Cisco
Same as Microsoft but for IT.
- Impossible Foods IPO
I've been vegetarian for 10 years and Impossible Burgers has been one of the most mindblowing experiences of my life. The product is phenomenal and on a league of its owned compared to Beyond Meat. IMHO Beyond taste like cheap school lunchroom burgers and Impossible tastes like something I would be excited to feed my family. If their pork products are great then I am ALL in because Chicken products are by far the easiest thing to replicate. I'm extremely excited about this product.
- Visa
They make a ton of money on transactions. I saw them hiring for blockchain development so it leads me to believe that they're adapting.
- Square
I work in the fintech space and I like their modest approach to financial services. Their acquiring of a bank charter is actually incredibly important due to all the procurement and legal processes that go behind being a fintech company (abiding by federal security laws, etc). The one reason I like Chase banking is because I enjoy their app. I see Square as a competitor to Chase, surprisingly.
- Apple
Apple designs its products with customer service in mind. I think the future of education technology will likely go to Apple because of this. Their screens and cameras are wonderful and I can see them pioneering computer vision products because of this. They are THE American Tech company.
- TMobile
Aggressive as hell and grew to be a large player through savvy moves across time. Their customer service is a highlight for me.
- JPM
Customer service for banking is unmatched IMO. If any legacy banker will make it across changes, I believe Chase is doing what it takes to adapt and think forward.
- Planet Fitness
$10 gyms, clean, and casual enough for the general population. You can't beat $10 gym membership when you're broke as fuck. I've been a heavy lifter before and still used Planet fitness in my transitions across states and whatnot. I need to look at their numbers more closely.
- Volkwagen
I trust Europe and Japan to take EVs more seriously. I don't know who will seriously come close to competing with Tesla in the long run but they'll have to.
- Panasonic
Panasonic, much like AMD, did not immediately reflect the value of what they have produced. AMD did not explode inline with bitcoin or cheaper GPU consumption, in the same way Panasonic did not reflect a massive spike in price after speculation in Tesla grew. They're an important arm to the EV market that spreads across many players ranging from Tesla to Toyota to big tech.

- Lyft
I think Lyft's focus on customer service and regional clientele will pay off against Uber, who is growing too quickly and spreading thin. Lyft will benefit from the development of computer vision and Big tech's interest in automanufacturing.

- Crypto (Bitcoin or XRP)
I like crypto as a technology as a software engineer. I see the value in a faster process for procuring and exchanging legal tender that does not have to go through the bottleneck of the ACH process or through legal issues like the PATRIOT ACT or the Bank Secrecy Act. It still fundamentally respects those laws without the frustrations of banking service bottlenecks. I think the halvening protocol has an interesting affect on Bitcoin and supply and the market that it's trying to generate.







-
submitted by codingprofessor to investing [link] [comments]

Mega eTextbooks release thread (part-28)! Find your textbooks here between $5-$25 :)

Please find the list below:
  1. Disease Gene Identification: Methods and Protocols, 2nd Edition: Johanna K. DiStefano
  2. Statistical Aspects of the Microbiological Examination of Foods, 3rd Edition: Basil Jarvis
  3. Revel for Social Problems, 14th Edition: Stanley Eitzen & Maxine Baca Zinn & Kelly Ei Smith
  4. Fundamentals of Human Resource Management: Pearson New International Edition, 3rd Edition: Gary Dessler
  5. Economics Today: The Micro View, 18th Edition: Roger LeRoy Miller
  6. Employment Law for Business, 8th Edition: Dawn Bennett-Alexander & Laura Hartman
  7. Surgical Exposures in Orthopaedics: The Anatomic Approach, 5th Edition: Stanley Hoppenfeld & Piet de Boer & Richard Buckley
  8. Project Management in Construction, 7th Edition: Sidney Levy
  9. Financial and Managerial Accounting, 7th Edition: John Wild & Ken Shaw & Barbara Chiappetta
  10. Handbook of Plant Disease Identification and Management, 1st Edition: Balaji Aglave
  11. Ubuntu Unleashed 2019 Edition: Covering 18.04, 18.10, 19.04, 13th Edition: Matthew Helmke
  12. Handbook of Insulin Therapies, 1st Edition: Winston Crasto & Janet Jarvis & Melanie J. Davies
  13. Python for Programmers: with Big Data and Artificial Intelligence Case Studies, 1st Edition: Paul J. Deitel & Harvey Deitel
  14. Medical Ethics: Accounts of Ground-Breaking Cases, 7th Edition: Gregory Pence
  15. Human Resource Management, 13th Edition: Gary Dessler
  16. The Biology and Therapeutic Application of Mesenchymal Cells, 2 Volume Set, 1st Edition: Kerry Atkinson
  17. Computer Security Fundamentals, 3rd Edition: William Chuck Easttom
  18. Hendee's Radiation Therapy Physics, 4th Edition: Todd Pawlicki & Daniel J. Scanderbeg & George Starkschall
  19. Nutrient Delivery, 1st Edition: Alexandru Grumezescu
  20. Technology Entrepreneurship: Taking Innovation to the Marketplace, 2nd Edition: Thomas N. Duening & Robert A. Hisrich & Michael A. Lechter
  21. Chemistry of Metalloproteins: Problems and Solutions in Bioinorganic Chemistry, 1st Edition: Joseph J. Stephanos & Anthony W. Addison
  22. Mathematical Statistics with Applications in R, 2nd Edition: Kandethody M. Ramachandran & Chris P. Tsokos
  23. Diagnostic Imaging: Genitourinary, 3rd Edition: Mitchell E. Tublin
  24. Comprehensive Management of Arteriovenous Malformations of the Brain and Spine, 1st Edition: Robert F. Spetzler & Douglas S. Kondziolka & Randall T. Higashida & M. Yashar S. Kalani
  25. Digital Design: With an Introduction to the Verilog HDL, 5th Edition: M. Morris R. Mano & Michael D. Ciletti
  26. Plasmids: Biology and Impact in Biotechnology and Discovery, 1st Edition: Marcelo E. Tolmasky & Juan C. Alonso
  27. Consumer Behavior: Buying, Having, and Being, Global Edition, 12th Edition: Michael R. Solomon
  28. Project Management Case Studies, 5th Edition: Harold Kerzner
  29. Medical Phisiology: Principles for Clinical Medicine, 4th Edition: Rodney A. Rhoades & David R. Bell
  30. Essentials of Contemporary Management, 7th Edition: Gareth Jones & Jennifer George
  31. Harmony and Voice Leading, 4th Edition: Thomas E. Benjamin & Michael Horvit & Robert S. Nelson
  32. Principles of Economics, 2nd Edition: Lee Coppock & Dirk Mateer
  33. Oral Microbiology and Immunology, 2nd Edition: Richard J. Lamont & George N. Hajishengallis & Howard F. Jenkinson
  34. Magnetic Resonance Imaging of the Brain and Spine, 5th Edition: Scott W. Atlas
  35. Accounting Information Systems: Controls and Processes, 3rd Edition: Leslie Turner & Andrea B. Weickgenannt & Mary Kay Copeland
  36. Strategic Corporate Social Responsibility: Sustainable Value Creation, 5th Edition: David Chandler
  37. Julien's Primer of Drug Action: A Comprehensive Guide to the Actions, Uses, and Side Effects of Psychoactive Drugs, 14th Edition: Claire D. Advokat & Joseph Comaty & Robert Julien
  38. The Grand Chessboard: American Primacy And Its Geostrategic Imperatives, 1st Edition: Zbigniew Brzezinski
  39. The Cosmic Perspective: The Solar System, 8th Edition: Jeffrey O. Bennett & Megan O. Donahue & Nicholas Schneider & Mark Voit
  40. Ultrastructure Atlas of Human Tissues, 1st Edition: Fred Hossler
  41. Advances in the Biology and Management of Modern Bed Bugs, 1st Edition: Stephen L. Doggett & Dini M. Miller & Chow-Yang Lee
  42. Patterns of World History: Volume One: To 1600, 1st Edition: Peter von Sivers & Charles A. Desnoyers & George B. Stow
  43. Genitourinary Imaging: A Core Review, 1st Edition: Matthew Davenport
  44. Evidence-based Obstetrics and Gynecology, 1st Edition: Errol R. Norwitz & Carolyn M. Zelop & David A. Miller & David L. Keefe
  45. Zoology, 10th Edition: Stephen Miller & John Harley
  46. Radical and Reconstructive Gynecologic Cancer Surgery, 1st Edition: Robert Bristow & Dennis Chi
  47. Davis's Diseases & Disorders A Nursing Therapeutics Manual, 6th Edition: Marilyn Sawyer Sommers
  48. Management & Cost Accounting, 6th Edition: Alnoor Bhimani
  49. Elements of Modern Algebra, 8th Edition: Linda Gilbert
  50. Psychiatric & Mental Health Nursing, 4th Edition: Katie Evans & Debra Nizette & Anthony O'Brien
  51. Molecular Biology: Different Facets, 1st Edition: Anjali Priyadarshini & Prerna Pandey
  52. Elementary Number Theory, 7th Edition: David Burton
  53. Accounting Information Systems, 14th Edition: Marshall B. Romney & Paul J. Steinbart
  54. Microeconomics, Global Edition, 9th Edition: Robert Pindyck & Daniel Rubinfeld
  55. Psychiatric and Mental Health Nursing Demystified, 1st Edition: Jim Keogh
  56. Entrepreneurship, 10th Edition: Robert Hisrich & Michael Peters & Dean Shepherd
  57. Ganong's Review of Medical Physiology, 26th Edition: Kim E. Barrett & Susan M. Barman & Jason Yuan & Heddwen L. Brooks
  58. Textbook of Obstetrics and Gynaecology: A life course approach, 1st Edition: Eric A.P. Steegers & Bart C.J.M. Fauser & Carina G.J.M. Hilders
  59. Engineering Mechanics: Statics, 8th Edition: James L. Meriam & L. G. Kraige & J. N. Bolton
  60. Basic Concepts of Psychiatric-Mental Health Nursing, 8th Edition: Louise Rebraca Shives
  61. Beckmann and Ling's Obstetrics and Gynecology, 8th Edition: Robert Casanova
  62. Biology: Concepts and Applications, 10th Edition: Cecie Starr & Christine Evers & Lisa Starr
  63. Estimating in Building Construction, 9th Edition: Steven J. Peterson & Frank R. Dagostino
  64. The Big Back Book: Tips & Tricks for Therapists, 1st Edition: Jane Johnson
  65. University Physics with Modern Physics, 14th Edition: Hugh D. Young & Roger A. Freedman
  66. Poisoning and Drug Overdose, 7th Edition: Kent Olson & Ilene Anderson & Neal Benowitz & Paul Blanc
  67. Koneman's Color Atlas and Textbook of Diagnostic Microbiology, 7th Edition: Gary W. Procop
  68. Experimental Psychology, 7th Edition: Anne Myers & Christine H. Hansen
  69. Marketing: An Introduction, 13th Edition: Gary Armstrong & Philip Kotler
  70. Gray's Anatomy for Students: With Student Consult, 3rd Edition: Richard Drake & A. Wayne Vogl & Adam W. M. Mitchell
  71. Chestnut's Obstetric Anesthesia: Principles and Practice, 5th Edition: David H. Chestnut & Cynthia A Wong & Lawrence C Tsen & Warwick D Ngan Kee & Yaakov Beilin & Jill Mhyre
  72. Chemistry: The Molecular Science, 5th Edition: John W. Moore & Conrad L. Stanitski
  73. Head, Neck and Dental Emergencies, 2nd Edition: Mike Perry
  74. Wong's Nursing Care of Infants and Children, 10th Edition: Marilyn J. Hockenberry & David Wilson
  75. Sports Emergency Care: A Team Approach, 3rd Edition: Robb Rehberg & Jeff G. Konin
  76. New Venture Creation: Entrepreneurship for the 21st Century, 10th Edition: Stephen Spinelli & Rob Adams
  77. Caring for the Vulnerable: Perspectives in Nursing Theory, Practice, and Research, 5th Edition: Mary de Chesnay & Barbara Anderson
  78. Geometry: The Line and the Circle: Maureen T. Carroll & Elyn Rykken
  79. Histories of Human Engineering: Tact and Technology: Maarten Derksen
  80. Land Restoration: Reclaiming Landscapes for a Sustainable Future, 1st Edition: Ilan Chabay & Martin Frick & Jennifer Helgeson
  81. Yamada's Handbook of Gastroenterology, 3rd Edition: Tadataka Yamada & John M. Inadomi & Renuka Bhattacharya & Jason A. Dominitz & Joo Ha Hwang
  82. Theoretical Physics 9: Fundamentals of Many-body Physics, 2nd Edition: Wolfgang Nolting & William D. Brewer
  83. Introduction to Programming with C++, 3rd Edition: Y. Daniel Liang
  84. Dental Emergencies, 1st Edition: Mark Greenwood & Ian Corbett
  85. Fundamentals of Physics and Chemistry of the Atmosphere, 2nd Edition: Guido Visconti
  86. Calculus: Early Transcendentals, 3rd Edition: William L. Briggs & Lyle Cochran & Bernard Gillett & Eric Schulz
  87. Educating Physical Therapists, 1st Edition: Gail Jensen
  88. Strategic Developments in Eurasia After 11 September, 1st Edition: Shireen Hunter
  89. Contemporary Issues in Healthcare Law and Ethics, 4th Edition: Dean Harris
  90. Transitioning from RN to MSN: Principles of Professional Role Development: Brenda Scott & Mindy Thompson
  91. Principles and Practice of Public Health Surveillance, 3rd Edition: Lisa M. Lee & Steven M. Teutsch & Stephen B. Thacker & Michael E. St. Louis
  92. Elementary Statistics: Picturing the World, 6th Edition: Ron Larson & Betsy Farber
  93. Human Sexuality in a World of Diversity, 6th Canadian Edition: Spencer A. Rathus & Jeffrey S. Nevid & Lois Fichner-Rathus & Alex McKay & Robin Milhausen
  94. Becoming Your Own Banker, 6th Edition: R. Nelson Nash
  95. Murach's MySQL, 3rd Edition: Joel Murach
  96. Intermediate Algebra, 13th Edition: Marvin L. Bittinger & Judith A. Beecher & Barbara L. Johnson
  97. Planning Health Promotion Programs: An Intervention Mapping Approach, 4th Edition: L. Kay Bartholomew Eldredge & Christine M. Markham & Robert A. C. Ruiter & Maria E. Fernández & Gerjo Kok & Guy S. Parcel
  98. Human Factors in Simple and Complex Systems, 3rd Edition: Robert W. Proctor & Trisha Van Zandt
  99. The Irony of Democracy: An Uncommon Introduction to American Politics, 17th Edition: Louis Schubert & Thomas R. Dye & Harmon Zeigler
  100. Understanding Earth, 7th Edition: John Grotzinger
  101. Nursing Research in Canada: Methods, Critical Appraisal, and Utilization, 4th Edition: Geri LoBiondo-Wood & Judith Haber & Cherylyn Cameron & Mina Singh
  102. The Philosophy of Film, 1st Edition: Thomas E. Wartenberg & Angela Curran
  103. Disaster Nursing and Emergency Preparedness, 4th Edition: Tener Goodwin Veenema
  104. Language in Mind: An Introduction to Psycholinguistics, 2nd Edition: Julie Sedivy
  105. Medical Anthropology: A Biocultural Approach, 3rd Edition: Andrea S. Wiley & John S. Allen
  106. Exploring Biology in the Laboratory, 3rd Edition: Murray P. Pendarvis & John L. Crawley
  107. Guide to Networking Essentials, 8th Edition: Greg Tomsho
  108. Social Psychology: A Storytelling Approach, 2nd Edition: Leonard Newman & Ralph Erber
  109. Managing Conflict: An Introspective Journey to Negotiating Skills, 1st Edition: Dorothy Balancio
  110. Environmental Change and Challenge: A Canadian Perspective, 5th Edition: Philip Dearden & Bruce Mitchell
  111. Brain and Behavior: A Cognitive Neuroscience Perspective, 1st Edition: David Eagleman & Jonathan Downar
  112. Cardiac/Vascular Nurse Exam Secrets Study Guide: Cardiac/Vascular Nurse Test Review for the Cardiac/Vascular Nurse Exam: Mometrix Media & Cardiac Vascular Nurse Exam Secrets
  113. Keeping the Republic: Power and Citizenship in American Politics, The Essentials, 9th Edition: Christine Barbour & Gerald Wright
  114. Principles of Environmental Science, 9th Edition: William Cunningham & Mary Cunningham
  115. Thomas' Calculus, 14th Edition: Joel R. Hass & Christopher E. Heil & Maurice D. Weir
  116. Pharmacology for Canadian Pharmacy Technicians, 1st Edition: Leland Norman Holland & Michael P. Adams & Jeanine Lynn Brice & Heather V. LeBlanc
  117. Cellular and Molecular Immunology, 9th Edition: Abul K. Abbas & Andrew H. Lichtman & Shiv Pillai
  118. Operations Management: Processes and Supply Chains, 11th Edition: Lee J. Krajewski & Manoj K. Malhotra & Larry P. Ritzman
  119. Jews, Christians, Muslims: A Comparative Introduction to Monotheistic Religions, 2nd Edition: John Corrigan & Frederick Denny & Martin S Jaffee & Carlos Eire
  120. Professional Nursing: Concepts & Challenges, 9th Edition: Beth Black
  121. Practical Homicide Investigation: Tactics, Procedures, and Forensic Techniques, 4th Edition: Vernon J. Geberth
  122. Fundamentals of Modern Manufacturing: Materials, Processes and Systems, 7th Edition: Mikell P. Groover
  123. Genetics: A Conceptual Approach, 7th Edition: Benjamin A. Pierce
  124. Computer Science Illuminated, 7th Edition: Nell Dale & John Lewis
  125. The Globalization of World Politics: An Introduction to International Relations, 8th Edition: John Baylis & Steve Smith & Patricia Owens
  126. Behavioral Neuroscience, 9th Edition: S. Marc Breedlove & Neil V. Watson
  127. Canadian Human Resource Management: A Strategic Approach, 12th Edition: Hermann Schwind & Krista Uggerslev & Terry Wagar & Neil Fassina
  128. Brief Principles of Macroeconomics, 9th Edition: N. Gregory Mankiw
  129. Living in the Environment, 4th Canadian Edition: G. Miller & Dave Hackett & Carl Wolfe
  130. Principles of Economics, 9th Edition: N. Gregory Mankiw
  131. Principles of Microeconomics, 9th Edition: N. Gregory Mankiw
  132. Child Development, 9th Edition: Laura E. Berk
  133. Home, School, and Community Collaboration: Culturally Responsive Family Engagement, 4th Edition: Kathy Beth Grant & Julie A. Ray
  134. Set Lighting Technician's Handbook, 4th Edition: Harry Box
  135. Clinical Nurse Leader Certification Review, 2nd Edition: Cynthia R. King
  136. Basic Chemistry, 4th Edition: Karen C. Timberlake & William Timberlake
  137. Sparks & Taylor's Nursing Diagnosis Pocket Guide, 3rd Edition: Linda Phelps
  138. Family Theories: Foundations and Applications, 1st Edition: Katherine R. Allen & Angela C. Henderson
  139. The Earth and Its Peoples: A Global History, 7th Edition: Richard Bulliet & Pamela Crossley & Daniel Headrick & Steven Hirsch & Lyman Johnson
  140. Sociology in Action: A Canadian Perspective, 3rd Edition: Tami Bereska & Diane Symbaluk
  141. Operations Management: Processes and Supply Chains, 12th Edition: Lee J. Krajewski & Manoj K. Malhotra & Larry P. Ritzman
  142. Introduction to Food Science and Food Systems, 2nd Edition: Rick Parker & Miriah Pace
  143. Liaisons, Student Edition: An Introduction to French, 3rd Edition: Wynne Wong & Stacey Weber-Fève & Bill VanPatten
  144. Zuckerman Parker Handbook of Developmental and Behavioral Pediatrics for Primary Care, 4th Edition: Marilyn Augustyn & Barry Zuckerman
  145. Teaching in Today's Inclusive Classrooms: A Universal Design for Learning Approach, 3rd Edition: Richard M. Gargiulo & Debbie Metcalf
  146. The Biological Basis of Mental Health, 3rd Edition: William T. Blows
  147. Developing and Managing Electronic Collections: The Essentials: Peggy Johnson
  148. Western Civilization: Volume II: Since 1500, 10th Edition: Jackson J. Spielvogel
  149. Talking to Strangers: What We Should Know about the People We Don't Know, 1st Edition: Malcolm Gladwell
  150. Understanding Pathophysiology, 7th Edition: Sue E. Huether & Kathryn L. McCance
  151. Our Environment: A Canadian Perspective, 5th edition: Dianne Draper & Ann Zimmerman
  152. Criminal Law: Cases and Materials, 8th Edition: John Kaplan & Robert Weisberg & Guyora Binder
  153. A Photographic Atlas of Histology, 2nd Edition: Michael J Leboffe
  154. Dragons and Tigers: A Geography of South, East, and Southeast Asia, 3rd Edition: Barbara A. Weightman
  155. Climate Change Biology, 1st Edition: Jonathan A. Newman & Madhur Anand & Hugh A. L. Henry & Shelley L. Hunt & Ze'ev Gedalof
  156. The Power of Critical Thinking: 5th Canadian Edition: Chris MacDonald and Lewis Vaughn
  157. Principles of Fire Behavior and Combustion, 4th Edition: Richard Gann & Raymond Friedman
  158. Informatics Nurse Exam Secrets Study Guide: Informatics Test Review for the Informatics Nurse Certification Exam: Informatics Exam Secrets Test Prep Team
  159. General Chemistry, 10th Edition: Darrell Ebbing & Steven D. Gammon
  160. A Practical Guide to Computer Forensics Investigations, 1st Edition: Darren R. Hayes
  161. Basic Biomechanics, 8th Edition: Susan Hall
  162. Essay Writing for Canadian Students, 8th Edition: Roger Davis & Laura K. Davis
  163. Biology, 11th Edition: Peter Raven & George Johnson & Kenneth Mason & Jonathan Losos & Susan Singer
  164. Molecular Imaging, 1st Edition: Ralph Weissleder& Brian D. Ross & Alnawaz Rehemtulla & Sanjiv Sam Gambhir
  165. Criminology, 4th Edition: Frank Schmalleger
  166. A Theory of Truthmaking: Metaphysics, Ontology, and Reality: Jamin Asay
  167. The Routledge Handbook of Metaphysical Grounding, 1st Edition: Michael J. Raven
  168. Linear Algebra and Its Applications, 5th Edition: David C. Lay & Steven R. Lay & Judi J. McDonald
  169. Essentials of Human Communication, 9th Edition: Joseph A. DeVito
  170. Economics: Principles, Applications, and Tools, 9th Edition, Global Edition: Arthur O'Sullivan & Steven Sheffrin & Stephen Perez
  171. Global Health 101, 3rd Edition: Richard Skolnik
  172. Mathematical Proofs: A Transition to Advanced Mathematics, 4th Edition: Gary Chartrand & Albert D. Polimeni & Ping Zhang
  173. Concepts in Strategic Management and Business Policy: Globalization, Innovation and Sustainability, 15th Edition, Global Edition: Thomas L. Wheelen & J. David Hunger & Alan N. Hoffman & Charles E. Bamford
  174. Chemistry: The Central Science, 14th Edition, Global Edition: Theodore E. Brown & H. Eugene LeMay & Bruce E. Bursten & Catherine Murphy & Patrick Woodward & Matthew E. Stoltzfus
  175. Biopsychology, 10th Edition, Global Edition: John P. J. Pinel & Steven Barnes
  176. Electric Circuits, 11th Edition: James W. Nilsson & Susan Riedel
  177. Keeping the Republic; Power and Citizenship in American Politics, the Essentials, 8th Edition: Christine Barbour & Gerald C Wright
  178. Applied Behavior Analysis: Pearson New International Edition, 2nd Edition: John O. Cooper & Timothy E. Heron & William L. Heward
  179. Cryptography and Network Security: Principles and Practice, 7th Edition, Global Edition: William Stallings
  180. Operating Systems: Internals and Design Principles, 9th Edition, Global Edition: William Stallings
  181. Options, Futures, and Other Derivatives, 9th Edition, Global Edition: John C. Hull
  182. Invitation to the Psychology of Religion, 3rd Edition: Raymond F. Paloutzian
  183. Valuation: The Art and Science of Corporate Investment Decisions, 3rd Edition: Sheridan Titman
  184. Comprehensive Clinical Nephrology, 5th Edition: Richard J. Johnson & John Feehally & Jurgen Floege
  185. Miller & Freund's Probability and Statistics for Engineers, 9th Edition, Global Edition: Richard Johnson & Irwin Miller & John Freund
  186. Exploring Strategy: Text and Cases, 11th Edition: Gerry Johnson & Richard Whittington & Patrick Regnér & Kevan Scholes & Duncan Angwin
  187. Economics for Business, 7th Edition: John Sloman
  188. Essentials of Economics, 7th Edition: John Sloman & Dean Garratt
  189. Economics, 9th Edition: John Sloman & Dean Garratt & Alison Wride
  190. Essential Economics for Business, 5th Edition: Johnsloman & Jones Elizabeth
  191. Finite Mathematics, 7th Edition: Stefan Waner & Steven Costenoble
  192. The SAGE Encyclopedia of Surveillance, Security, and Privacy, 1st Edition: Bruce A. Arrigo
  193. Evolution, 4th Edition: Douglas J. Futuyma & Mark Kirkpatrick
  194. Adult Development and Aging, 7th Edition: John C. Cavanaugh & Fredda Blanchard-Fields
  195. Foundations of Finance, 9th Edition, Global Edition: Arthur J. Keown & John D Martin & J. William Petty
  196. Learning PHP, MySQL & JavaScript: With jQuery, CSS & HTML5, 4th Edition: Robin Nixon
  197. Head First Learn to Code: A Learner's Guide to Coding and Computational Thinking, 1st Edition: Eric Freeman
  198. Learning Swift: Building Apps for macOS, iOS, and Beyond, 3rd Edition: Jonathon Manning & Paris Buttfield-Addison & Tim Nugent
  199. Database Systems: Design, Implementation, & Management, 12th Edition: Carlos Coronel & Steven Morris
  200. Introduction to Solid Modeling Using SolidWorks, 13th Edition: William Howard & Joseph Musto
  201. Communications Receivers: Principles and Design, 4th Edition: Ulrich Rohde & Jerry Whitaker & Hans Zahnd
  202. Connect Core Concepts in Health, 15th Edition: Paul Insel & Walton Roth
  203. On Course: Strategies for Creating Success in College and in Life, 8th Edition: Skip Downing
  204. Vander's Human Physiology, 15th Edition: Eric Widmaier & Hershel Raff & Kevin Strang
  205. Biology, 4th Edition: Robert Brooker & Eric Widmaier & Linda Graham & Peter Stiling
  206. The Essentials of Statistics: A Tool for Social Research, 4th Edition: Joseph F. Healey
  207. Oracle 12c: SQL, 3rd Edition: Joan Casteel
  208. Global Business Today, 10th Edition: Charles Hill & G. Tomas M. Hult
  209. Project Management: The Managerial Process, 7th Edition: Erik Larson & Clifford Gray
  210. Organizational Behavior: A Practical, Problem-Solving Approach, 2nd Edition: Angelo Kinicki & Mel Fugate
  211. International Management: Culture, Strategy, and Behavior, 10th Edition: Fred Luthans & Jonathan Doh
  212. CorelDRAW X8: The Official Guide, 12th Edition: Gary David Bouton
  213. Physics for Scientists and Engineers: An Interactive Approach, 2nd Edition: Robert Hawkes & Javed Iqbal & Firas Mansour & Marina Milner-Bolotin & Peter Williams
  214. Programmable Logic Controllers, 5th Edition: Frank Petruzella
  215. Foundations in Microbiology, 10th Edition: Kathleen Park Talaro & Barry Chess
  216. Applied Numerical Methods with MATLAB for Engineers and Scientists, 4th Edition: Steven Chapra
  217. Tonal Harmony, 8th Edition: Stefan Kostka & Dorothy Payne & Byron Almén
  218. Discrete Mathematics, 8th Edition: Richard Johnsonbaugh
  219. Bates' Pocket Guide to Physical Examination and History Taking, 8th Edition: Lynn S. Bickley
  220. NANDA International Nursing Diagnoses: Definitions & Classification 2018-2020, 11th Edition: T. Heather Herdman & Shigemi Kamitsuru & Heather T. Herdman
  221. Biology: Concepts and Investigations, 4th Edition: Mariëlle Hoefnagels
  222. Biology: Concepts and Investigations, 3rd Edition: Mariëlle Hoefnagels
  223. Human Biology: Concepts and Current Issues, 8th Edition, Global Edition: Michael D. Johnson
  224. Messages: Building Interpersonal Communication Skills, 5th Canadian Edition: Joseph A. DeVito & Rena Shimoni & Dawne Clark
  225. The Interpersonal Communication Book, 14th Edition, Global Edition: Joseph A. DeVito
  226. Computational Systems Pharmacology and Toxicology, 1st Edition: Rudy J Richardson & Dale E Johnson & Noffisat Oki & David Faulkner
  227. Shelly Cashman Series Microsoft Office 365 & Office 2019 Introductory, 1st Edition: Sandra Cable & Steven M. Freund & Ellen Monk & Susan L. Sebok & Joy L. Starks
  228. The Practice of Emotionally Focused Couple Therapy: Creating Connection, 2nd Edition: Susan M. Johnson
  229. The Marriage Clinic: A Scientifically Based Marital Therapy, 1st Edition: John M. Gottman
  230. Cognitive-Behavioral Therapy with Couples and Families: A Comprehensive Guide for Clinicians, 1st Edition: Frank M. Dattilio & Aaron T. Beck
  231. International Marketing, 17th Edition: Philip R. Cateora & John Graham & Mary C Gilly
  232. Kaplan and Sadock's Concise Textbook of Clinical Psychiatry, 3rd Edition: Benjamin Sadock & Virginia Alcott Sadock
  233. Anthropology, 14th Edition: Carol R. Ember & Melvin Ember & Peter N. Peregrine
  234. The Men They Will Become: The Nature And Nurture Of Male Character: Eli Newberger
  235. Accounting, 27th Edition: Carl S. Warren & James M. Reeve & Jonathan Duchac
  236. ICD-10-CM 2019: The Complete Official Codebook, 1st Edition: American Medical Association
  237. Essentials of Human Anatomy & Physiology, 12th Edition, Global Edition: Elaine N. Marieb & Suzanne M. Keller
  238. Early Childhood Education Today, 14th Edition: George S Morrison
  239. Programming Bitcoin: Learn How to Program Bitcoin from Scratch, 1st Edition: Jimmy Song
  240. The Physiology and Biochemistry of Prokaryotes, 4th Edition: David White & James Drummond & Clay Fuqua
  241. Environmental Microbiology, 3rd Edition: Ian L. Pepper & Charles P. Gerba & Terry J. Gentry
  242. Industrial Microbiology: An Introduction, 1st Edition: Michael J. Waites & Neil L. Morgan & John S. Rockey & Gary Higton
  243. Introduction to Econometrics, Updated 3rd Edition, Global Edition: James H. Stock & Mark W. Watson
  244. Introduction to Econometrics, 3rd Edition: James H. Stock & Mark W. Watson
  245. Expert Oracle Application Express, 2nd Edition: Doug Gault & Dimitri Gielis & Martin DSouza & Roel Hartman
  246. The Art of Reasoning: An Introduction to Logic and Critical Thinking, 4th Edition: David Kelley
  247. Physics, 5th Edition: James S. Walker
  248. Applied Fluid Mechanics, 7th Edition: Robert L. Mott & Joseph A. Untener
  249. Applied Strength of Materials, SI Units Version, 6th Edition: Robert L. Mott & Joseph A. Untener
  250. Social Psychology, 12th Edition: David Myers & Jean Twenge
  251. Applied Strength of Materials, 6th Edition: Robert Mott & Joseph A. Untener
  252. Foundations of Nursing Research, 7th Edition: Rose Marie Nieswiadomy & Catherine Bailey
  253. Molecular Cell Biology, 8th Edition: Harvey Lodish & Arnold Berk & Chris A. Kaiser & Monty Krieger & Anthony Bretscher
  254. Machine Elements in Mechanical Design, 6th Edition: Robert L. Mott & Edward M. Vavrek & Jyhwen Wang
  255. DeVita, Hellman, and Rosenberg's Cancer, 11th Edition: Vincent T. DeVita & Steven A. Rosenberg & Theodore S. Lawrence
  256. Particle Image Velocimetry: A Practical Guide, 3rd Edition: Markus Raffel & Christian E. Willert & Fulvio Scarano & Christian J. Kähler
  257. Smith's Textbook of Endourology, 4th Edition: Arthur D. Smith & Glenn Preminger & Gopal H. Badlani & Louis R. Kavoussi
  258. College Algebra with Modeling & Visualization, 6th Edition: Gary K. Rockswold
  259. Financial Accounting Theory, 7th Edition: William R. Scott
  260. Biology Now, 2nd Edition: Anne Houtman & Megan Scudellari & Cindy Malone
  261. Psychological Science, 5th Edition: Michael Gazzaniga & Diane Halpern
  262. The Handbook of Technical Writing, 11th Edition: Gerald J. Alred & Charles T. Brusaw & Walter E. Oliu
  263. A Graphical Approach to College Algebra, 6th Edition: John Hornsby & Margaret L. Lial & Gary K. Rockswold
  264. Business Analytics, 4th Edition: Jeffrey D. Camm & James J. Cochran & Michael J. Fry & Jeffrey W. Ohlmann
  265. Biological Psychology, 13th Edition: James W. Kalat
  266. Business Communication Today, 14th Edition: Courtland L. Bovee & John V. Thill
  267. Geosystems Core, 1st Edition: Robert W. Christopherson & Stephen Cunha & Charles E. Thomsen & Ginger Birkeland
  268. Principles of Information Security, 6th Edition: Michael E. Whitman & Herbert J. Mattord
  269. Financial & Managerial Accounting, 14th Edition: Carl S. Warren & James M. Reeve & Jonathan Duchac
  270. Corporate Finance: Theory and Practice, 5th Edition: Pierre Vernimmen & Pascal Quiry & Maurizio Dallocchio & Yann Le Fur & Antonio Salvi
  271. Introductory Statistics, 10th Edition: Neil A. Weiss
  272. Introduction to Cryptography: Principles and Applications, 3rd Edition: Hans Delfs & Helmut Knebl
  273. Business Essentials, 8th Canadian Edition: Ronald J. Ebert & Ricky W. Griffin & Frederick A. Starke & George Dracopoulos
  274. Introduction to Mathematical Statistics, 8th Edition: Robert V. Hogg & Joseph W. McKean & Allen T. Craig
  275. The Routledge Companion to Business Ethics, 1st Edition: Eugene Heath & Byron Kaldis & Alexei Marcoux
  276. Geosystems An Introduction to Physical Geography, Global Edition, 9th Edition: Ginger H. Birkel & Robert W. Christopherson
  277. Scientific American Environmental Science for a Changing World, 2nd Edition: Jeneen InterlandI & Anne Houtman
  278. Precalculus, 10th Edition: Ron Larson
  279. The Human Brain Book: An Illustrated Guide to its Structure, Function, and Disorders, New Edition: Rita Carter
  280. Introduction to Materials Science for Engineers, 8th Edition: James F. Shackelford
  281. Adobe Dreamweaver CC Classroom in a Book, 1st Edition: Jim Maivald
  282. Trigonometry, 11th Edition: Margaret L. Lial & John Hornsby & David I. Schneider & Callie Daniels
  283. Investment Banks, Hedge Funds, and Private Equity, 3rd Edition: David P. Stowell
  284. Cognitive Neuroscience: The Biology of the Mind, 5th Edition: Michael Gazzaniga & Richard B. Ivry & George R. Mangun
  285. Cognitive Neuroscience: The Biology of the Mind, 5th Edition: Michael Gazzaniga & Richard B. Ivry (Author), George R. Mangun (Author)
  286. Project Management Theory and Practice, 3rd Edition: Gary L. Richardson & Brad M. Jackson
  287. Organic Chemistry: Structure and Function, 8th Edition: K. Peter C. Vollhardt & Neil E. Schore
  288. Read, Reason, Write: An Argument Text and Read, 11th Edition: Dorothy Seyler
  289. Fundamentals of Management: Management Myths Debunked!, Global Edition, 10th Edition: Stephen P Robbins & David A. De Cenzo & Mary Coulter
  290. Computer Networking: A Top-Down Approach, Global Edition, 7th Edition: James Kurose & Keith Ross
  291. An Introduction to Banking: Principles, Strategy and Risk Management, 2nd Edition: Moorad Choudhry
  292. The Immune System, 4th Edition: Peter Parham
  293. Biochemistry: Concepts and Connections, Global Edition, 1st Edition: Dean R. Appling & Spencer J. Anthony-Cahill & Christopher K. Mathews
  294. Writing about Writing, 3rd Edition: Elizabeth Wardle & Douglas Downs
  295. Data Wrangling with JavaScript, 1st Edition: Ashley Davis
  296. Experience Psychology, 4th Edition: Laura King
  297. An Introduction to Mathematical Statistics: Fetsje Bijma & Marianne Jonker & Aad van der Vaart & Reinie Erné
  298. Business Communication: Polishing Your Professional Presence, 3rd Edition: Barbara G. Shwom & Lisa Gueldenzoph Snyder
  299. Earth's Evolving Systems: The History of Planet Earth, 2nd Edition: Ronald E. Martin
  300. Business Ethics: Decision Making for Personal Integrity & Social Responsibility, 4th Edition: Laura Hartman & Joseph DesJardins & Chris MacDonald
  301. College Algebra and Trigonometry, Global Edition, 6th Edition: Margaret L. Lial & John Hornsby & David I. Schneider & Callie Daniels
  302. Essentials of MIS, 12th Edition: Kenneth C. Laudon & Jane P. Laudon
  303. Behavior Analysis and Learning: A Biobehavioral Approach, 6th Edition: W. David Pierce & Carl D. Cheney
  304. University Physics, 14th Edition: Hugh D. Young & Roger A. Freedman
  305. Earth System History, 4th Edition: Steven M. Stanley & John A. Luczaj
  306. Analytical Mechanics, 2nd Edition: Nivaldo A. Lemos
  307. Fundamentals of Management, 7th Canadian Edition: Stephen P. Robbins & David A. DeCenzo & Mary Coulter
  308. Computer Accounting with QuickBooks Online: A Cloud Based Approach, 2nd Edition: Carol Yacht & Susan Crosson
  309. Cost Accounting and Financial Management for Construction Project Managers, 1st Edition: Len Holm
  310. Business Continuity Management in Construction, 1st Edition: Leni Sagita Riantini Supriadi & Low Sui Pheng
  311. Contemporary Logistics, 12th Edition, Global Edition: Paul R. Murphy & A. Michael Knemeyer
  312. Mechanical Engineers' Handbook, Volume 1: Materials and Engineering Mechanics, 4th Edition: Myer Kutz
  313. Mechanical Engineers' Handbook, Volume 2: Design, Instrumentation, and Controls, 4th Edition: Myer Kutz
  314. Mechanical Engineers' Handbook, Volume 3: Manufacturing and Management, 4th Edition: Myer Kutz
  315. Mechanical Engineers' Handbook, Volume 4: Energy and Power, 4th Edition: Myer Kutz
  316. An Introduction to Mathematical Statistics and Its Applications, 6th Edition: Richard J. Larsen & Morris L. Marx
  317. Developmental Mathematics, 1st Edition: Robert F. Blitzer
  318. Thinking Mathematically, 7th Edition: Robert F. Blitzer
  319. Wardlaw's Contemporary Nutrition, 10th Edition: Anne Smith & Angela Collene
  320. Mathematical Statistics: An Introduction to Likelihood Based Inference, 1st Edition: Richard J. Rossi
  321. Asking the Right Questions, 11th Edition: M. Neil Browne & Stuart M. Keeley
  322. Asking the Right Questions, 11th Edition, Global Edition: M. Neil Browne & Stuart M. Keeley
  323. Crash Course Cardiology, 4th Edition: Antonia Churchhouse & Julian O. M. Ormerod & Michael Frenneaux
  324. A Graphical Approach to Precalculus with Limits, 7th Edition: John Hornsby & Margaret L. Lial & Gary K. Rockswold
  325. Unlocking Equity and Trusts, 5th Edition: Mohamed Ramjohn
  326. Public Speaking: The Evolving Art, 4th Edition: Stephanie J. Coopman & James Lull
  327. Social Psychology, 8th Edition: Michael Hogg & Graham Vaughan
  328. Human Resources Management in Canada, 12th Canadian Edition: Gary Dessler & Nita Chhinzer & Nina Cole
  329. Law Core Textbook Bundle: Equity and Trusts, 8th edition: Alastair Hudson
  330. Living Ethics: An Introduction with Readings: Russ Shafer-Landau
  331. Microsoft Project 2019 Step by Step, 1st Edition: Cindy Lewis & Carl Chatfield & Timothy Johnson
  332. Global Business Ethics: Responsible Decision Making in an International Context, 1st Edition: Ronald D Francis & Guy Murfey
  333. Construction Management: Theory and Practice, 1st Edition: Chris March
  334. Harrison's Endocrinology, 4th Edition: J. Larry Jameson
  335. Harrison's Neurology in Clinical Medicine, 4th Edition: Stephen Hauser & S. Andrew Josephson
  336. English Grammar Workbook For Dummies with Online Practice, 3rd Edition: Geraldine Woods
  337. Naked: The Dark Side of Shame and Moral Life, 1st Edition: Krista K. Thomason
  338. Ashcraft's Pediatric Surgery, 6th Edition: George W. Holcomb III & J. Patrick Murphy & Daniel J Ostlie
  339. Mobile Apps Engineering: Design, Development, Security, and Testing, 1st Edition: Ghita K. Mostefaoui & Faisal Tariq
  340. Lange Clinical Neurology, 10th Edition: Roger Simon & David Greenberg & Michael Aminoff
  341. International Textbook of Diabetes Mellitus, 2 Volume Set, 4th Edition: R. A. DeFronzo & E. Ferrannini & Paul Zimmet & George Alberti
  342. Java Programming, 9th Edition: Joyce Farrell
  343. Discovering Behavioral Neuroscience: An Introduction to Biological Psychology, 4th Edition: Laura Freberg
  344. How the Immune System Works, 5th Edition: Lauren M. Sompayrac
  345. Fundamentals of Electroceramics: Materials, Devices, and Applications, 1st Edition: R. K. Pandey
  346. Essentials of Hospital Neurology, 1st Edition: Karl E. Misulis & E. Lee Murray
  347. Biology of Humans: Concepts, Applications, and Issues, 6th Edition: Judith Goodenough & Betty A. McGuire
  348. Williams Textbook of Endocrinology, 13th Edition: Shlomo Melmed & Kenneth S. Polonsky & P. Reed Larsen & Henry M. Kronenberg
  349. Financial Management: Principles and Applications, Global Edition, 13th Edition: Sheridan Titman & Arthur J. Keown & John D Martin
  350. Case Studies in Immunology: A Clinical Companion, 7th Edition: Raif S. Geha & Luigi Notarangelo
  351. Handbook of MRI Technique, 4th Edition: Catherine Westbrook
  352. MRI: Basic Principles and Applications, 5th Edition: Brian M. Dale & Mark A. Brown & Richard C. Semelka
  353. Robbins Basic Pathology, 10th Edition: Vinay Kumar & Abul K. Abbas & Jon C. Aster & Vinay Kumar & Abul K. Abbas & Jon C. Aster
  354. Rosen's Emergency Medicine: Concepts and Clinical Practice: 2-Volume Set, 9th Edition: Ron Walls & Robert Hockberger & Marianne Gausche-Hill
  355. BNF for Children: 2018-2019, 1st Edition: Paediatric Formulary Committee
  356. Sitaraman and Friedman's Essentials of Gastroenterology, 2nd Edition: Shanthi Srinivasan & Lawrence S. Friedman
  357. Practical Gastroenterology and Hepatology Board Review Toolkit, 2nd Edition: Kenneth R. DeVault & Michael B. Wallace & Bashar A. Aqel & Keith D. Lindor
  358. Reinforcement Learning: An Introduction, 2nd edition: Richard S. Sutton & Andrew G. Barto
submitted by bookseller10 to Textbook_releases [link] [comments]

Solid Trust Pay - zřízení peněženky TwentyXpro English Business Plan - Work at Home - Bitcoin BTC SolidTrustPay STP PerfectMoney PM Amazing5 Review - Which payment processor? PerfectMoney Payeer Bitcoin Payza SolidTrustPay AdvCash How Use Solid Trust Pay Card to Withdrawal Cash From ATM Solid Trust Pay - Secure Trusted Payment Processor

Try making a cross-exchange through Neteller, pre-checking if Bitcoin can exchange to Neteller and Neteller to Solid Trust Pay USD or any other currency. You can also find some private offers from people on the forum. Probably someone of the forum members will help you to exchange Bitcoin to Solid Trust Pay USD. As mentioned earlier, you can also transfer bitcoin to solid trust pay without facing any trouble. Solid trust pay makes payment system more reliable in a way that you don't need any registration in order to transfer money from one solid trust pay account to another one. This can be the reason that most people choose it. Try making a cross-exchange through Neteller, pre-checking if Solid Trust Pay USD can exchange to Neteller and Neteller to Bitcoin or any other currency. You can also find some private offers from people on the forum. Probably someone of the forum members will help you to exchange Solid Trust Pay USD to Bitcoin. The services offered by SolidTrust Pay include online merchant accounts for eCommerce, international money transfers for business or remittances, cross-border bill payments, Bitcoin exchanges and ... Exchange Solid Trust Pay to Bitcoin. Here are all options for exchange Solid Trust Pay USD to Bitcoin BTC. The best exchange options with the perfect exchange rate are placed at the top of the monitoring table. All exchangers are verified by administrator so the exchangers monitor contains only trust exchangers with a perfect reputation.

[index] [31424] [585] [18455] [578] [8627] [11009] [11037] [11572] [1266] [30359]

Solid Trust Pay - zřízení peněženky

Just got my Solid Trust Pay Payroll card to get My Advertising Pays withdrawals in 3 days - Duration: 1:25. rob fraser 3,118 views. 1:25. Why You Shouldn't Pay Off ... How to Use a Bitcoin ... Open Solid Trust Pay account here: https://www.solidtrustpay.com/ref/96752 Solid Trust Pay - Secure Trusted Payment Processor Need Bitcoin Account? Visit htt... 🔴 Facebook CEO Mark Zuckerberg interview: Bitcoin BTC Event & Facebook news updates [April,2020] Facebook US 14,587 watching Live now The TOP 5 Oil Stocks to Buy for 2020 (High Growth ... How To Withdraw from Solid Trust Pay To Your Bank Account - Duration: 7:07. Alex Goddard Recommended for you. ... Coinbase - online peněženka pro bitcoin - Duration: 6:19. eMamina 1,473 views. PerfectMoney Payeer Bitcoin Payza SolidTrustPay AdvCash Here is my views on the payment processors Amazing5 offers investors. For me personally I find SolidTrust Pay to fast and secure with low ...

http://gpu-miningbitcoin.forexbrokereview.com