every.channel/evolution/proposals/ECP-0016-mdns-peer-discovery.md
2026-02-15 16:17:27 -05:00

1.1 KiB

ECP-0016: mDNS peer discovery for gossip

Status

Draft

Context

Manual gossip peers are a barrier for LAN onboarding. iroh already supports an mDNS-based address lookup, which can discover endpoints on the local network without external infrastructure.

Decision

Enable iroh's mDNS address lookup and use it as a peer discovery layer for catalog gossip. When gossip starts (or sharing announces), we probe mDNS for a short window and merge any discovered endpoints into the peer list.

Details

  • Enable iroh feature address-lookup-mdns.
  • Advertise UserData = "every.channel" for local discovery filtering.
  • When gossip is started, probe for ~2 seconds and merge discovered endpoints with configured peers.
  • mDNS discovery is best-effort; failures should not block manual peers.

Consequences

  • LAN nodes can connect and discover each other without copying addresses.
  • Global discovery still requires at least one public peer.

Follow-ups

  • Add a UI indicator when mDNS peers are found.
  • Evaluate relay-less LAN mode and mDNS-only sessions for local-first setups.