# Protocol

- [Gateway](/docs/protocol/gateway.md): Contracts with endpoints for querying
- [Send](/docs/protocol/gateway/send.md): Endpoint to request query
- [Receive](/docs/protocol/gateway/receive.md): Endpoints that receive query results from Relayer
- [Estimate fee](/docs/protocol/gateway/estimate-fee.md): Calculate the fees required for query
- [Cache](/docs/protocol/gateway/cache.md): Reuse data acquired in the past
- [Light Client](/docs/protocol/light-client.md): Light Client is a contract that verifies proof and extracts data
- [Request Query](/docs/protocol/light-client/request-query.md): Processing performed by Light Client at the time of request
- [Verify](/docs/protocol/light-client/verify.md): Function to verify proof
- [Estimate fee](/docs/protocol/light-client/estimate-fee.md): Calculate the fees required for query
- [Relayer](/docs/protocol/relayer.md): Relayer is responsible for retrieving data and proof of other chains
- [Konoha](/docs/protocol/konoha.md): Konoha is a module for retrieving the appropriate block header for each ecosystem
- [Chainlink Oracle](/docs/protocol/konoha/chainlink-oracle.md)
- [Herodotus](/docs/protocol/konoha/herodotus.md)
- [Lagrange](/docs/protocol/konoha/lagrange.md)