Hardcore disassembly of Kadena, a PoW public chain that runs 1,000 chains in parallel

Hello everyone

I am Bagot

A leek that wants to become the Buffett of the cryptocurrency world

Recently, Kadena, which was publicly raised on the compliant platform Coinlist, launched its mainnet. Kadena is a very distinctive project and has previously received investments from many well-known funds, including Multicoin Capital, Metastable, SVangel, Scalar Capital, etc.

What makes Kadena different from all current public chains is that it is not just a public chain, but a blockchain network that can interconnect public chains with consortium chains/private chains.

Moreover, Kadena adopts the PoW consensus, which means that it is CPU mining in the early stage. Now that the main network has just been launched, personal computers should be able to participate in mining and earn KDA.

With doubts, I read their white paper and some social information and wrote this article.

What is Kadena?

Kadena is a blockchain network that can interconnect consortium chains/private chains and other public chains. In order to interconnect them, Kadena designed the parallel chain proof-of-work architecture Chainweb based on PoW consensus , the enterprise private chain Kuro based on the ScalableBFT consensus protocol, and developed the Turing-incomplete, simple and readable smart contract language Pact .

These all seem to be very innovative designs. While most mainstream public chains currently use PoS consensus, Kadena has chosen PoW, which seems to have similar concepts and features to Nervos and Conflux.

The Turing-incomplete Pact smart contract language has aroused people's interest in it. The official said that this is a human-readable contract language.

Human readable??

Through Chainweb and Pact, Kadena can connect consortium chains and public chains and support mutual calls, pioneering the inclusion of consortium chains into the cross-chain system.

What is Chainweb?

Source: Chainweb Protocol Security Computation White Paper

Chainweb is a new parallel chain proof-of-work architecture that can integrate hundreds or thousands of individually mined parallel chains into a single network. Parallel chains can interact with the Merkle tree roots of other parallel chains to enforce a super chain.

According to the description in the white paper, Chainweb is scalable. As the number of parallel chains increases, its processing capacity per second will also increase. With such an architecture, Chainweb has the potential to grow to at least 1,250 chains, and the TPS can reach more than 10,000 .

How does Chainweb achieve high TPS?

The design of Chainweb draws on Bitcoin's Simplified Payment Verification (SPV ). Each parallel chain in the network mines the same cryptocurrency (KDA), which can be transferred and linked together through trustless, simple payment verification (SPV) at the smart contract level.

Briefly explain what SPV is?

The Bitcoin white paper states:

Payments can be verified without running a full network node. A user needs to keep a copy of the longest proof-of-work chain's block headers, and can keep querying the network until it is confident that it has the longest chain and can follow the merkle branch leading to the transaction that was timestamped and included in the block.

Source: Bitcoin White Paper

In the Chainweb network, the nodes of parallel chains only need to synchronize and confirm the block header information of other parallel chains . Each chain integrates a subset of the Merkle tree roots of other parallel chains in its own block hash, which can verify that it has completed certain workloads, thereby achieving Kadena's scalability.

This picture may be able to express its logic very vividly.

source:

https://explorer.chainweb.com/mainnet

Taking this picture as an example, I captured the transaction of Chain4 with a block height of "145676". It synchronized the information of the previous blocks Chian1, Chain2, Chain4, and Chain9 by default, including one of its own chains and three parallel chains. The other three parallel chains synchronized the block header information of the four parallel chains of the previous block respectively. In this way, the block header information of the 10 parallel chains is equivalent to verification.

Perhaps it can be understood in this way that Chianweb is equivalent to having 10 Bitcoin networks here, each of which independently generates blocks, thereby increasing the block generation speed of the entire network, and then interconnecting and verifying them through the SPV idea.

Of course, I also have some questions, such as how many nodes are there on each chain? How to ensure the security of each chain by parallel block generation? ?

Turing-incomplete smart contract language Pact

Kadena has launched a new smart contract language, Pact, which is an interpreted language that can be executed directly on the chain. The Pact code will be a human-readable smart contract.  

Source: https://pact.kadena.io/

Pact is not only applicable to public chains, but will also be open to enterprises, who can directly and clearly write smart contracts securely on the blockchain.

Officials said that the design of Pact benefited from existing smart contracts, namely Bitcoin and Ethereum, as well as stored procedure languages, SQL and LISP. They believe that Turing completeness will bring many potential risks, such as the Dao hack incident on Ethereum.

Pact is Turing-incomplete, which helps prevent recursion bugs and related bad usage patterns. In Pact, any recursion detected immediately raises a fault and terminates all running code. This feature can greatly reduce the potential attacks that may exist in smart contracts.

Currently, Pact has built a Pact version Kadenamint for Cosmos based on the Tendermint protocol, which will become a bridge between Kadena and Cosmos in the future. At the same time, it has signed an agreement with the Web3 Foundation to study the integration of Pact into the Polkadot ecosystem.

Interestingly, the entire architecture of Kadena is mainly written in the Haskell programming language. Haskell is a relatively niche language, but many engineers who have used it highly recommend it.

A few months ago, I chatted with a friend who was a senior engineer in a blockchain project and asked him what his favorite programming language was. He told me that " Haskell is the most awesome language ", which left a deep impression on me about Haskell.

When I told him about the Kadena project, he was very excited to find that Kadena was written in Haskell, and told me that Kadena introduced the Z3 theorem prover, which should be very powerful. (Note: Z3 is a high-performance theorem proving program developed by Microsoft Research)

Kadena Token Economic Model

Kadena’s token economic model and usage are similar to those of Ethereum, and are also used for transfers, creation of smart contracts, and payment of contract execution fees.

source:

https://www.theblockbeats.com/news/4450

This is the token distribution model made by BlockRhythm based on the published information. The total amount of KDA is 1 billion, 700 million of which are allocated to miners through mining output . Half of the remaining tokens will be released every 20 years. It is estimated that about 200 million KDA will be in circulation in early 2021.

The platform has reserved 200 million tokens for future ecological development, and officials said that 2 to 5 of these tokens will not be unlocked.

Other unlock information is as follows.  

source:

https://www.theblockbeats.com/news/4450

Kadena's valuation is not low. Based on the public offering price of 0.5 USD and 1 USD, it has a valuation of 500 million to 1 billion USD. Currently, KDA is not listed on the exchange for circulation. It is expected that 300 million KDA will be in circulation at the beginning of next year, and the circulating market value will also be around 300 million USD.

What opportunities do you have?

Kadena's solution is very innovative. It increases the blockchain's transaction volume per second through the parallel chain proof-of-work architecture Chainweb, while also using the SPV approach to achieve cross-chain verification.

Kadena has also developed a new smart contract language Pact, which is currently being used in consortium chains and is also collaborating with Cosmos and Polkadot.

The overall valuation of the project may be high at present, but the proportion of financing is not very high, and the total amount is released through mining at a constant rate .

It might be good to participate in mining early on , and there will definitely be mining farms coming in later. The secondary market is currently unknown, and the official said that it will be launched on Coinlist's trading platform first.

Welfare

We are honored to invite Will Martino, the founder of Kadena, to share his experience in the Bajue community at 11:00 am tomorrow. If you are interested in Kadena, please feel free to learn more and ask questions.

for example:

1. How does Kadena design its own technical architecture to interconnect the public chain and the consortium chain?

2. Why choose the PoW consensus mechanism, and how to improve TPS?

3. What mining algorithm is used? Can I mine with my PC now?

4. Why is the Pact language Turing incomplete?

...

More questions waiting for you to ask~