Decentralised Oracle

In ABCI 2.0, the introduction of ExtendVote method that allows validator nodes to extend the data provided in their vote in the precommit stage at block h-1.

The data in the extension is not interpreted by CometBFT, but it is signed, making it verifiable by other nodes. At block h, the data will be available at proposal stage to be injected into transactions to be verified by the other validators of the network.

D-Chain oracle module supports applications to register their required and expected data types to be included in their deployed smart contracts. A typical usage of this will be market data where at least 2/3 of the validators have seen and added their data in the signed extension, allowing the aggregation of offchain data to be used as onchain states.

Apart from fetching data from providers, offchain compute is also supported. This maybe in TEE enclaves or other secure compute environments. This is particularly useful for notarisation of large documents without going through centralised services.

Cosmos Adoption of decentralised oracles

At the time of writing, examples of the use of these methods for price oracle is already deployed on dydx and Neutron.