Authority Discovery¶
Questions¶
Is the authority discovery implemented on Kademlia for a custom peer discovery?¶
No, it uses Kademlia capabilities however it adds a custom handlers for DHT Events, like: DhtEvent::ValueFound - DhtEvent::ValueNotFound - DhtEvent::ValuePut - DhtEvent::ValuePutFailed - DhtEvent::PutRecordRequest
These events are produced by the Discovery layer (Kademlia) and propagated to the authority-discovery that handles each of them. Specifically for DhtEvent::PutRecordRequest it does a validation step and then store the record.
What happens is that the authority-discovery is the actual protocol implementation for discovery in substrate/polkadot given that it produces and store the records that are available in the DHT for other peers to query, validate and use.
What are the functionalities of the authority discovery, beyond discovery new peers based on its authority ids?¶
- Publish the node external address, more specifically, create the authority discovery record, sign it and distributing through DHT allowing other nodes to query it.
- Handle DHT events, validating incoming records and caching other authorities address.
What subsystems uses the authority discovery mechanism? Describe the usages.¶
- Availability Distribution
- Availability Recovery
- Gossip Support
Check if we can currently extend the authority discovery protocol can to golang kademlia p2p library¶
Yes, we pretty much can implement the protocol. - We are able to encode the records using the same proto schema used by substrate/polkadot - We can query for specific keys in DHT. - What can write a custom validator to validate incoming records. - golang-libp2p does not works in the same way rust-libp2p works by enabling us to receive those DHT events but we can achieve the same protocol implementation using what the library provide to us.