The Interoperable State Machine Protocol (ISMP) is a lightweight, unopinionated messaging protocol designed to facilitate the creation of cross-chain applications. ISMP relies on consensus and state proofs to authorize the execution of cross-chain requests. In doing so, ISMP is able to provide the same degree of security as the underlying blockchains it connects.
ISMP is lightweight API surface area and is therefore easy to use. Its lightweight design means that ISMP is able to verify proofs even within expensive environments such as Ethereum. In addition, ISMP offers a familiar and easy-to-understand message-passing mechanism that facilitates two types of requests: GET and POST. What is contained in these requests and how they are interpreted is up to you (and whoever you’re sending them to). These messages could be in XML, Binary encoded, JSON, etc.
How to get started
We have guides to get you started with ISMP. Check out our integration guides for help getting started!
pallet-ismp
ismp-solidity-v0
Relaying MessagesRequests & Responses