Cross-chain messaging protocols have become increasingly popular over the past year.
Wormhole recently surpassed 1 billion cross-chain messages since its launch in 2021 and has seen a total volume of over $39 billion being transferred through its token bridge.
Similarly, interchain transactions on and active addresses on Axelar have increased by 478% and 430% over the past year, respectively.
The primary method for transferring information and assets across different blockchain networks today is through blockchain bridges. However, bridges are infamously challenging to decentralize.
Blockchain bridges often use the lock and mint or burn and mint approach to transfer value across different blockchains.
In doing so, a user must lock up their native asset on Chain A and swap it for a synthetic version of that same asset before they can transfer it from Chain A to Chain B. Once they transfer the asset, they must once again pay to change that synthetic asset back to the native asset on Chain B.
Although this method would guarantee instant finality on the destination chain, the process is rather tedious. It also comes with its own set of security risks, such as being vulnerable to malicious attacks.
Wormhole itself was subjected to one of these attacks in 2022, where the protocol lost over $320 million in ether, making it one of the largest DeFi exploits to date.
Read more: Most bridges ‘absolutely not secure’: Chainlink co-founder
Custodial bridges have hoped to prevent this by introducing a centralized entity that oversees the assets and safeguard the bridge itself. However, this in turn means that users must place their trust in a single entity, defying the ethos of decentralization.
Another way that bridges are able to transfer assets is by having a unified liquidity pool. This means that multiple chains will share the same liquidity pool and improve capital efficiency between the connected blockchains.
This solution would only work if all chains could fulfill liquidity requests. In the instance where multiple transactions are hoping to withdraw from the same pool, there must be ways to ensure that there is enough liquidity in the pool to fulfill all requests. Failure to do so could result in greater complications. This type of bridging also does not guarantee instant finality.
The latest shift toward focusing on cross-chain messaging solutions is to improve existing bridging infrastructure.
It is important to note that cross-chain messaging protocols are low-level infrastructures, similar to blockchains themselves, Robinson Burkey, the CCO at the Wormhole Foundation, told Blockworks.
“These messaging protocols provide the basic language and framework to send data securely between two systems that aren’t compatible. Once you have this foundational technology in place you can build what people often refer to as token bridges, on top of the messaging protocol,” Burkey said.
A popular cross-chain messaging solution that has gained attention is Axelar’s General Message Passing (GMP).
GMP acts almost like a translator for the different networks that otherwise would not be able to understand each other. This is achieved through self-executing smart contracts that are able to use various methods to validate and authenticate transactions on Chain A before they reach Chain B.
Galen Moore, the global communications lead at Interop Labs, the initial developer of the Axelar network, told Blockworks that GMP simplifies the blockchain bridging process by enabling developers on one chain to call functions on a different chain.
“GMP allows applications to bridge assets, alongside instructions for an application on another blockchain,” Moore said. “If I build an app on a new blockchain and use a simple bridge, I have to say to my users, “Bridge your ETH to my blockchain over here, then use this DEX to buy some of my gas tokens over there, then come back to my app and onboard.” GMP can trigger all those steps automatically; to the user, it looks like a single transaction.”
Although GMP is an improvement over bridges when it comes to transferring assets, it too is still in its infancy.
“GMP is an improvement, but it’s still a great deal of work to create a unified user experience that spans multiple blockchains,” Moore said.
He notes that the next stage of evolution for Axelar will be to enable programmable interoperability, which will have the potential to leave bridges behind altogether.
“When the interoperability layer itself is a virtual machine like Ethereum, it can automate complex tasks – like minting a token on multiple blockchains at once, and managing supply and custom features across all of them,” Moore said.
Moore notes the interchain token service (ITS) that launched on Axelar mainnet last week is hoping to provide this exact type of automation.
“The vision behind Axelar is a Web3 where developers can compose freely, connecting to functions and networks that exist on many chains across Web3 and beyond. This is something you just can’t do at all in Web2. The long-term vision is an internet that supports a different breed of online network,” he said.
Wormhole is also working to improve the interoperability experience. Recently revealing its ZK roadmap to facilitate multichain communication to improve the trust assumptions on the Wormhole protocol.
“In our approach, ZK will serve as a cornerstone for decentralization and ensuring message verification. Specifically, in an interoperability protocol like Wormhole, ZK will empower the prover to authenticate the entire state of a blockchain, such as Ethereum, to verify the validity of messages transmitted from the source blockchain,” Burkey said.
He adds, “The ZK roadmap will become clearer in the upcoming months. But our strategy involves bringing aboard new cryptography experts to our team and collaborating, upcoming light client rollouts, and a strategic collaboration with a hardware provider to accelerate a number of light client implementations.”