Technical deconstruction of CKB public chain: why it can speed up BTC legitimacy layer 2

Source: Chainview

When I first heard that @NervosNetwork was fighting to make BTC layer2, I was not surprised. Because CKB public chain technology is close to BTC but ahead of BTC, it can not only inherit native UTXO features, but also achieve more advanced programmable feature expansion. If it is almost impossible for the CKB public chain to surpass the narrative of BTC, then the next best thing is that its layer 2 of BTC will definitely be invincible. Why? Next, let’s talk about my opinion on CKB.

The current BTC layer2 market is limited by the flaws in the verification capabilities of the BTC main network, and there is a situation where hundreds of flowers are blooming. Yes, it is precisely because the BTC mainnet script language is inherently simple, and its calculation + verification capabilities are almost close to 0, that it gives the market space and opportunities to fully exert itself. At present, in addition to limited transaction signature verification + multi-signature within the UTXO unlocking conditions, the BTC main network cannot directly implement complex transaction logic such as data data and state changes that need to be verified. Instead, BTC can only be As an asset settlement layer, a powerful public chain is extended to build local consensus and computable verification capabilities to achieve expansion. As a result, there is no unified standard for the implementation of BTC layer 2, there is no "legitimacy", and it is even difficult to distinguish between superior and inferior. The difference between the narrow sense and the broad sense can only be distinguished based on the perception of the community: In the narrow sense, only the extension scheme guaranteed by the Lightning Network status channel and RGB's one-time sealing Single Seal is the real BTC legitimacy layer 2, because they are fully The application takes advantage of BTC's limited script verification capabilities and does not require or rely on a minimal degree of off-chain local consensus. Broadly speaking, as long as the local consensus of the extended chain is recognized, there is a cross-chain bridge solution to ensure the safe migration of assets. In theory, the current Ethereum EVM chain, Solana high-concurrency performance chain, etc. can serve as layer 2 of BTC. Obviously, the current BTC layer2 market is obviously polarized. It is either extremely narrow, with slow and difficult development like the Lightning Network and RGB, or extremely broad, and all performance chains that can achieve safe asset interaction with the BTC main network can be called It is BTC layer2. So, is there no "compromise" solution? Yes, the answer is: @NervosNetwork  whose underlying technology framework follows the UTXO model and has adapted and upgraded performance. Specific performance:

1) CKB Network and BTC are completely the same in terms of "UTXO model, mining consensus mechanism", etc. Different from the account balance model of mainstream public chains such as Ethereum, UTXO has certain unique advantages. It has certain advanced features in terms of transaction privacy, flexible transaction construction, and parallel processing to prevent double spending. It can be called Satoshi Nakamoto’s greatest invention. This also explains why, after Ethereum, Sui and Aptos have adopted similar UTXO models. We can say that Bitcoin’s capacity and block production speed have limitations of the times, but the UTXO model is very advanced. CKB follows the UTXO model and optimizes and upgrades it to the Cell model, which not only retains the transaction purity of the Bitcoin UTXO model, but also provides the data status of account models such as Ethereum. To understand it in layman’s terms: the creation and destruction of the Bitcoin UTXO model is similar to the process in which coins are continuously destroyed and minted. Cell eliminates the destruction process and wants to verify and preserve the state for a long time. Each Cell contains two fields: Capacity and Data. Capacity is equivalent to the balance of UTXO in bytes; Data stores any form of data such as historical transaction status; this allows the Cell collection to not only accurately express balances but also handle asset transfers. , and can also include a series of complex states of smart contracts. In general, the Cell model is a leading trading model that is more sustainable, more flexible, and can expand the scope of application of the UTXO model. It is also the key to CKB being able to inherit the security of the BTC main network while “speeding up” the slow expansion directions of Bitcoin such as Lightning Network and RGB.

2) Take the recent launch of RGB++ by CKB as an example. According to the normal process, the BTC ecosystem will extend a mature RGB solution. The difficulty is not the one-time sealing process of the BTC main network, but precisely the off-chain process. The client verifies the process of communication, coordination and joint state maintenance between nodes, especially when the nodes are decentralized. In other words, RGB theory looks easy, but in practice it is limited by limitations such as basic infra, which leads to many obstacles.

CKB sees this clearly and simply allows all nodes that perform off-chain client verification to participate in CKB’s on-chain public verification process. This directly speeds up the practical path of the UTXO extension client that RGB wants to implement. After all, the complex P2P node network consensus in the off-chain client environment is difficult to achieve and is full of complexity and challenges. For example, off-chain communication may face data synchronization delays or inconsistencies, as well as some fraud and attack challenges, etc. It would be much simpler if this process could be copied to the on-chain environment. 3) RGB++ has been discussed a lot recently. I will add an Open Transaction data format proposed by CKB, so that everyone can feel the advanced characteristics of the CKB chain. To put it simply: Open Transaction allows multiple participants to construct and aggregate different transactions at different times, including three major features: partial construction, modification allowed, incremental construction and aggregation. For example: Alice creates an Open Transaction and declares how much token A she wants to exchange from Bob for token B. After the transaction is initiated, it is still editable. If Bob agrees to the transaction conditions after receiving it, he can You can add your own token B and supplement the trading conditions. It may seem abstract at first glance. For example, in a cross-chain scenario, Alice and Bob can independently complete asset transactions on different heterogeneous chains, which greatly improves the cross-chain interoperability of the CKB chain; in a complex DeFi transaction scenario, DeFi that users participate in may need to be dynamically adjusted according to market changes. Through Open Transaction, contract participants can flexibly adjust transaction conditions during the contract execution process, which undoubtedly greatly enriches the complexity of transactions.

In my opinion, Open Transaction and UTXO transaction unlocking conditions are exactly the same. They can integrate the construction of complex transaction unlocking conditions, multi-party signature participation, complex application scenarios and other trading environments. They also follow the BTC main chain. Value innovation extended by ideas. above Interestingly, as a member of the Ethereum core R&D team, @busyforking’s first work was based on BTC’s UTXO model. Although Ethereum's smart contract model is now more widely used, Jan and his Nervos team paranoidly chose to extend and upgrade on top of BTC's UTXO model. It not only expresses awe for Satoshi Nakamoto’s minimalist UTXO transaction model, but also planted the seeds for it to become the BTC Native layer 2.

To summarize: I am very optimistic about CKB doing BTC layer2. In the short term, it can indeed speed up the implementation of Lightning Network and RGB on the UTXO model chain, and at least provide a meaningful reference for the expected implementation of these two types of orthodox expansion plans on the BTC mainnet; in the long term, CKB’s chain is native Features and underlying architecture innovation and compatibility will allow it to go further in this non-standard melee of BTC layer 2.

Note: There are still many technical details and highlights about CKB. I will take the time to further analyze more content. I can’t help but sigh. BTC layer2 has given some new chains the opportunity to rise up, and it has also given There are endless possibilities for old chains to sprout new ones.