Introduction to Avalanche

Avalanche introduces a new family of consensus protocols that are claimed to combine the best features of classic protocols and Nakamoto consensus. Described as ‘metastable’, the Avalanche protocol is actually four protocols that build upon each other. These are Slush, Snowflake, Snowball, and finally Avalanche itself

The consensus problem

Consensus is the most important goal that needs to be achieved when many computers in a distributed network work together on the same task. A typical example is a banking system that maintains account balances using multiple servers. Banks don’t rely on one single database to carry their data, but many geographically distributed machines across the globe to handle these transactions. Such system must make sure that its computers are all on the same page, so there are no undesired or unexpected situations where the same money, for example, can be spent twice.

This has been an important problem in Computer Science for a long time. In distributed systems, there exist only two viable solutions to this problem: classic protocols and Nakamoto consensus.

Classic consensus protocols

Classic consensus protocols were developed by two great computer scientists, Leslie Lamport and Barbara Liskov. They are both Turing Award winners which is equivalent to the Nobel Prize in Computer Science. The best features of these protocols include,

  • quick finality, and
  • quick guarantees about the committed transactions.

But this comes with two big trade offs,

  • such consensus model does not scale well beyond 1000 nodes, and
  • it requires everyone in the network to know all other participants.

In other words, it is a good choice if you are building a permissioned system but it is not a reliable foundation when you are in a dynamic environment of untrusted nodes.

Nakamoto consensus

The second family of consensus protocols appeared in 2009. Satoshi Nakamoto introduced Bitcoin which paved a way for a whole bunch of other similar protocols. The advantages of Nakamoto consensus are,

  • we don’t need all the nodes to participate in the consensus all the time, and
  • such system can scale to a large number of global nodes.

But, of course, everything comes with a price and Nakamoto consensus is no exception. The biggest drawbacks of Bitcoin are,

  • users have to wait for 10 to 60 minutes before their transactions are confirmed,
  • throughput is limited to 3-7 transactions per second which is insufficient for a global currency system;
  • Bitcoin consumes an enormous amount energy that is enough to power two countries like Denmark.

Avalanche

Avalanche was first proposed in a whitepaper released on May 16, 2018 in an IPFS link by a pseudonymous group of developers by the name of Team Rocket. Cornell professor Emin Gün Sirer assisted Team Rocket with some analysis, and context portions of the whitepaper, along with publicizing the protocol.

Features

According to the whitepaper, Avalanche combines the best of both classical consensus protocols and Nakamoto consensus, in particular,

  • quick finality and low latency: it takes about 2 seconds for your payment to be processed and verified;
  • higher throughput: from 1000 to 10,000 transactions per second;
  • robust: the network maintains undeniable consensus without knowing its participants;
  • green: there are no miners and all participants are of the same class.

Metastability

The whitepaper describes the protocol as metastable. Metastability is the core idea of Avalanche and implies an eventual absolute consensus of the system. This means that, given two choices, the network will always make a decision, i.e. all the nodes will eventually agree on the same thing.

The Avalanche family

Avalanche is a protocol that is comprised of four different protocols building upon each other: Slush, Snowflake, Snowball and Avalanche itself.

Slush

Slush is the basic protocol that combines the gossip protocol and the random subsampling procedure.

Let’s consider an example. A network that uses the Slush protocol needs to choose a color: blue or red.

  • An individual node randomly picks a small subset of nodes and asks them to choose a color.
  • The requesting node receives answers and bases its vote on the majority of received votes.
  • This process repeats itself for everybody else.

If you read the above attentively, you may have a question, ‘How does a node know they picked the right color?’ And the answer is that’s what the other protocols in the family are for.

Other notes:

  • There is no history, each node only knows their current color,
  • Slush is not Byzantine Fault Tolerant,
  • There is no guarantee the nodes will eventually come to an agreement, as they can continue flipping colors and maintain a 50/50 situation.

Snowflake

Snowflake is what gives Avalanche its Byzantine Fault Tolerance. Snowflake provides each node with a counter to store the number of consecutive samples of the network that have given the result of all red or all blue.

After a certain number of consecutive samples it accepts the colour for good. This allows correct nodes to commit and means that the nodes will come to consensus. If the streak is broken, then the counter returns to zero and starts again.

Snowball

Snowball builds upon Snowflake by adding in a state of confidence. It does this in order to make the protocol harder to attack, because it is now able to store information and make decisions based off that information that it was not able to before.

Snowball progresses Snowflake’s counters to ‘confidence counters’. These confidence counters mean that after each query that yields a result of either red or blue, the node increases its confidence counter by one. It switches colours if its confidence in the current colour goes below the confidence value of the other colour.

Instead of coming to a decision on a colour based on the number of consecutive results for a colour as per Snowflake, a node comes to a decision after a number of consecutive queries yield a result that means that nodes’ confidence in a colour exceeds that in other colours.

Avalanche

Avalanche, the final protocol, generalizes Snowball and maintains a dynamic append-only Directed Acyclic Graph (DAG) of all known transactions.

Append-only means that transactions only add on to previous ones. Each new transaction connects to one of the latest transactions.

A DAG is not entirely different from a blockchain and the only big difference is that a blockchain is linear, each new block points back to the single latest one. A DAG, however, is unbounded and can grow in multiple directions, as new transactions can attach to multiple previous transactions, which creates a web-like structure.

AVA token

The AVA token is what makes Avalanche a proof-of-stake system. Staking in Avalanche is the primary mechanism for preventing Sybil attacks, i.e. an attack on consensus by creating a big number of fake nodes. Unlike Ethereum and others, that stake is not a collateral and will never be lost. If you misbehave there is no risk of your money being taken from you. So the stake here is solely to make sure that you cannot impersonate other people. This is one of the great outcomes of the Avalanche protocol. Staking is not used for consensus, in fact, it is completely independent of it.

Conclusion

Avalanche tackles the consensus problem by introducing a clever combination of gossip protocols and recurring subsampling. And fair governance is achieved via sampling and staking resulting in a direct tie between users and their decisions. Avalanche is quite ambitious but we are yet to see an actual working implementation, as Ethereum’s lead developer Vlad Zamfir expressed his doubts concerning the probabilistic nature of the Avalanche consensus.

Read more

Snowflake to Avalanche

Protocol Spotlight: Avalanche

Demystifying Snowflake to Avalanche

NB. Do not confuse the protocol team with the namesake twitter account.

Related news

The Great AMA 2019: The Future of Blockchain Technology

Coinspeaker The Great AMA 2019: The Future of Blockchain TechnologyCredits Blockchain Platform has taken the initiative to hold its first wide-scale Ask Me Anything live session on the theme “The Future Of Blockchain Technology” that will take place on Sunday, September 1. The event will bring together representatives of such well-known companies as QuarkChain, Matic Network, and HoloChain.The venue will be the Chico Crypto YouTube Channel where there will be a businesslike conversation that will address several pressing subjects which are of interest to the vast proportion of the crypto community.Companies have expressed their willingness to hold the event given the need to jointly discuss ways to develop blockchain technology and its application in the current economic and political reality.Industry experts will come together to have a comprehensive discussion in the process of which they will answer numerous questions and share their vision for future opportunities. Questions and answers session will be moderated by Tyler Swope aka Chico Crypto, YouTube blogger, and die-hard crypto investor.Igor Chugunov, CEO & Founder of Credits:“Such events make it possible to engage in discussion not only the leaders of the crypto industry but also an audience interested and somehow involved in our global technology. The questions that will be presented are related to the entire crypto market, and the answers to which will allow us to understand and evaluate the current prospects for the development of future technology.”Credits Blockchain Platform is an open-source high-speed technological innovation that enables users to use its blockchain platform as a perfect solution for the business and IT industry through autonomous smart contracts for creating and storing data about transactions and operations throughout the network.QuarkChain is a growth company that provides a secure blockchain solution for various types of projects. It is one of the first public chains that successfully implemented state sharing technology for blockchain. QuarkChain is able to support multiple virtual machines (VMs), various consensus algorithms, different ledger formats and even multi-native tokens in one network.Matic Network is a blockchain scalability platform which provides secure, scalable and instant transactions powered by PoS side chains and an adapted version of Plasma. The company provides payment APIs/SDKs for DApps, merchant, and users to instantly accept or pay in crypto assets like ERC20 tokens, ETH, and others.Holochain is an open source framework for building fully distributed, peer-to-peer applications in JavaScript or Lisp provided with company’s core services: a customizable UI, the Holochain DPKI app that manages keys and identities across Holochain applications, the Holo platform for serving crypto apps to normal web browsers, API bridges between crypto apps, and the capacity to migrate data when updating distributed apps.The Great AMA 2019: The Future of Blockchain Technology
Coinspeaker

WordProof and WORBLI Partner To Bring Online Content Transparency Using Blockchain TechnologyWordProof and WORBLI Partner To Bring Online Content Transparency Using Blockchain Technology - Blockchain News

The post WordProof and WORBLI Partner To Bring Online Content Transparency Using Blockchain Technology written by Richard Kastelein appeared first on Blockchain News - Blockchain News and Opinion - Security and Utility Tokens, Tokenomics, Cryptoeconomics Enterprise Blockchain platform WORBLI has partnered with online content startup WordProof and now, via WORBLI’s platform, WordProof’s users are able to timestamp their content, enabling true ownership, trust and proof of content authenticity. WORBLI CEO and Co-founder Domenic Thomas mentioned: “With the recent impetus from blockchain technology, we now have the unprecedented ability to have […] The post WordProof and WORBLI Partner To Bring Online Content Transparency Using Blockchain Technology written by Richard Kastelein appeared first on Blockchain News - Blockchain News and Opinion - Security and Utility Tokens, Tokenomics, Cryptoeconomics Blockchain News - WordProof and WORBLI Partner To Bring Online Content Transparency Using Blockchain Technology
Blockchain News

Hot news

By continuing to browse, you agree to the use of cookies. Read Privacy Policy to know more or withdraw your consent.