The First Cross-Chain Assets Router — SubBridge launched on Phala, Bridging Parachain, EVM, and Other Chains
We are excited to announce that the new product of Phala Network’s Decentralized Computation cloud platform, SubBridge has launched! It is the first cross-chain router in the substrate ecosystem, which will bridge Parachain, EVM, and other chains.
As one of the most important products of Phala, SubBridge, based on the “XCM + ChainBridge cross-chain protocol” to realize cross-chain transmission of assets and information has support for parachain- EVM currently. More chains will be supported in the near future.
SubBridge’s launch means a lot to parachains including Phala Network and other chains. Now Parachains can integrate and use the capability of SubBridge, break the barriers among different ecosystems (e.g. EVM), further enhancing Polkadot’s prosperity. Likewise Phala, the interaction border will be expanded, and the application scenarios of assets in dApps will be richer. For other chains’ ecosystems, with the link of SubBridge can realize its ecological link with parachains, and the ecological complementarity.
How Does SubBridge Work?
Unlike any standalone bridge, SubBridge is a cross-chain assets router linking different bridges. It is composed of the individual cross-chain bridges and the routing module.
For example, the individual bridges, XCM and ChainBridge, support the direct transfer between Khala and parachains and external chains. The bridges are connected to the routing module to enable the core feature, routed transfer from one to another blockchain via Khala, for example, to bridge an asset from a parachain to Ethereum.
With the direct and routed transfer, SubBridge enables asset transfer from one chain to any other chains which have been registered.
The above figure shows a typical life cycle of a routed transfer: from a Parachain to an EVM chain via SubBridge on Khala.
When a cross-chain transfer is initiated from a parachain, it’s wrapped into a standard Polkadot XCM message and posted to Khala. Khala then decodes the message and decides how to execute the transfer operation. Then SubBridge kicks in. It checks the payment destination in the XCM message. If the destination points to a local address on Khala, the assets will be deposited into the local account. Otherwise, it can also encode a path pointing to an address by another bridge. Then the transaction will be routed to the target blockchain (e.g. Ethereum) by a bridge automatically.
Similarly, when a cross-chain transfer is initiated from an EVM chain, the ChainBridge module receives that. Then SubBridge will resolve the destination address, and process the transfer in the same way as before. For example, when the destination path encodes an address on a parachain, SubBridge will forward it to the parachain by XCM.
Now, You can transfer PHA between Khala⇔Karura and Khala⇔Ethereum on the Phala App.
Why Phala does such work
On the road of cross-chain, Phala’s team has been exploring for nearly two years.
- In Dec. 2020, based on XCM, Phala and Acala unveiled the first-ever cross-chain demo on the Rococo testnet V0, realizing the token transfer from Acala to Phala on Rococo.
- In Aug. 2021, based on ChainBridge, Phala’s canary network Khala Network launched Khala⇔Ethereum Bridge. As the first parachain⇔Ethereum bridge on Substrate, PHA can be transferred between Ethereum and Khala.
Phala Team gained many precious experiences in developing a cross-chain tool, and believes the realization of cross-chain asset router is of great ecological significance.
Exploring More Partners
As of now, parts of parachains have expressed that they want to connect with SubBridge, and the related work is being carried out in an orderly manner. Phala will optimize the SubBridge based on the tech foundation, and provide its excellent cross-chain capability to all the blockchains.
Phala Network tackles the issue of trust in the computation cloud.
Organizing a decentralized network of computation nodes around the world, it offers high-performance services without relying on any cloud vendor. Phala workers run the programs in Secure Enclaves, a privacy technology already embedded into modern processors, enabling versatile and confidential execution. Together, this creates the infrastructure for a powerful, secure, and scalable trustless computing cloud.