Cross-chain transactions, aggregation and reconstruction under "modularity"

Brief analysis of the development of cross-chain aggregation.

Written by: Cabin Crew

Whether it is asset cross-chain or information/data cross-chain, there are too many cross-chain bridges and various cross-chain protocols on the market. According to chainspot, there are currently about 114 cross-chain bridges and more than 130 networks on the market. The road is crowded.

Under such a background, cross-chain aggregation is just needed. Regardless of asset cross-chain or data/information cross-chain, how to better integrate various cross-chain solutions such as official bridges and third-party bridges and introduce more liquidity is a problem that cross-chain aggregators need to solve.

Before discussing cross-chain aggregators, let’s define and classify cross-chain methods. 1kx research partner Dmitriy Berenzon once gave a more authoritative explanation on cross-chain bridges:

A "bridge" is defined as a system for transferring information between two or more blockchains. Information can refer to assets, contract calls, identities, or states.

It can be simply understood that the cross-chain bridge allows any data, including tokens, chain status, contract calls, and even identity certificates, NFTs, governance votes, etc., to be transmitted from the source chain to the target chain, so that assets and data can be transferred between different Free circulation on the blockchain. Two chains can have different protocols, rules and governance models. The cross-chain bridge enables both parties to interoperate in a communicative, compatible, and secure manner.

Most of the early cross-chain bridges were mainly asset cross-chains, and data/information cross-chains required more complex structures and designs. To observe a cross-chain bridge, it is often necessary to discuss several of its main components:

(1) Monitoring: Responsible for monitoring the status on the source chain and smart contract function calls, often participated by roles such as Oracle, Validator or Relayer.

(2) Consensus (may have): In some modes, before the information is relayed to the target chain, the relay node reaches a consensus on the correctness of the relayed message.

(3) Message transmission/relay: After the monitoring role receives the event, it transmits the message from the source chain to the destination chain.

(4) Signature: The relay node signs the message and encrypts the information sent to the target chain (as part of an individual or multi-signature, etc.).

Looking at the different blockchain frameworks and structures corresponding to the cross-chain method, we can better observe the functions and innovations of a cross-chain product:

• Application layer: Asset cross-chain bridge
• Data transmission layer: message cross-chain protocol
• Trust Layer: inter-chain trust mechanism
• **Incentive layer: **Trust layer or transmission layer may involve incentives, which can be observed separately

The Trust Layer is very important to the cross-chain protocol. The design of the trust mechanism will make trade-offs among factors such as security, cost, delay, and expense during information transmission. It is an important position in the technological innovation of cross-chain projects.

The development of cross-chain aggregation products relies on the development of the cross-chain bridge ecology itself, and requires various cross-chain bridges to have a certain degree of maturity in order to be able to produce more complete products.

After 2022, with the continuous progress of the cross-chain bridge project, the update of the modular blockchain concept, and the development of new technologies such as ZK, there are many cross-chain bridge solutions based on different needs, and cross-chain transaction aggregators (such as LI FI, etc.) ) is increasing in maturity;

The message cross-chain protocol has also received attention in the primary market and has received a good valuation. In the general interoperability solution represented by LayerZero, within the framework of LayerZero, neither the relay (Relayer) nor the predictor (Oracle) has formed any consensus or verification, and only transmits information, becoming a cross-platform without native consensus system. Chain protocol, enlightening the market.

CabinVC organizes information on current representative projects such as multi-chain bridges/cross-chain aggregators/cross-chain information protocols, including LayerZero, Socket, XY Finance, O3 Swap, Chainswap, Multichain, and LiFi protocol, which can be used in this track Carry out simple valuation benchmarking and project comparison:

However, general cross-chain message passing may not be the so-called "cross-chain end". In some innovative cross-chain projects, the concept of modular blockchain has also influenced this track, trying to break through the "impossible triangle of interoperability" and bring more possibilities to cross-chain.

The Interoperability Impossibility Triangle:

• • trustless: has the same security as the underlying domain;*
• Scalability: any domain can be supported;
• *Information versatility: able to process arbitrary cross-domain data. *

Some projects are innovating in cross-chain communication protocols and cross-chain aggregators based on modular ideas. Think modularly.

In the modular interoperability protocol, the structure of the bridge can be simply split into:

• Application Application
• Verify Verification
• Transport Transport

Among them, the application layer and the transport layer can be shared to adapt to the existing application paradigm. At the same time, if the verification layer is configured for the modular interoperability protocol, based on the various verification mechanisms currently available, it can also increase the actual Programmability in the direction of use cases, transaction amounts, transaction delays, etc.

However, this composable approach requires the bridge to mix and match various verification methods with different structural parts of the blockchain and ensure the effective transmission of information. In various verification methods, the execution layer verifies the validity through ZK proof, which can simplify the entire verification process.

Based on the above ideas, you can pay attention to the following more innovative cross-chain ideas:

IBC-based modular network protocol Polymer

Polymer was originally developed based on the Cosmos ecosystem, and extended cross-chain communication to outside the Cosmos ecosystem through ZK-IBC (inter-blockchain communication). As a multi-chain routing center, Polymer Chain builds a chain to host ZK light clients and OP fraud provers to verify transactions from any modular configuration, and supports communication between heterogeneous chains such as Ethereum.

Gnosis Chain's Hashi Aggregator

Hashi launched by Gnosis Chain is defined as an EVM hash oracle aggregator. Its main logic lies in "requiring information to be verified by multiple independent mechanisms instead of only one mechanism." Hashi allows the same message to be delivered in different ways. If the same message can appear on the target domain of multiple providers, it is considered correct; if a different message appears, it is resolved through the dispute resolution process.

Multi-Message Aggregation (MMA)

MMA is Uniswap's design in governance cross-chain messaging. It aims to pass the commands of the Ethereum mainnet to Uniswap in other non-L2 EVM chains for deployment. It is regarded as an additional security module for cross-chain communication. Recently, Kydo from the Uniswap Accountability Committee recently proposed the idea of "using the client of the protocol as a bridge": it is planned to use MMA to transfer N bridges from Ethereum to another chain with the same message. On the receiving chain, if there are k/N bridges delivering the same message, the message is executed.