Participation in an indexer federation

[gammazero]

Discovery

Indexers that participate in a federation should be explicitly configured to recognize/allow the other indexers, by peer ID. Indexers can sign messages and the signature can be verified using the peer ID. This will prevent unknown/unwanted indexers from joining the federation. Can indexers transitively trust each other? In other words, if A and B trust each other, and B and C trust each other, then do A trust C trust each other?

Indexers could use gossip pubsub to discover the addresses of other indexers, but that probably does not add significant value over the simplicity of explicitly configuring the peer addresses.

Data Sharing

Indexers within a federation should share

• Know providers
• IPFS advertisement cache nodes
• Any info needed for dividing keyspace (TBD)

When an indexer discovers a new provider, it tells its peers

When an indexer starts up it asks peers for providers and cache nodes.