Overview

Node discovery, channel discovery, and channel updates are broadcasted through gossip messages on the Lightning network. Rather than relying on a third-party to distribute information, Lightning relies on announcements containing information with network updates.

Details

Channel Discovery

To support channel discovery, three gossip messages are supported. Peers in the network exchange channel_announcement messages containing information regarding new channels between the two nodes. They can also exchange channel_update messages, which update information about a channel. There can only be one valid channel_announcement for any channel, but at least two channel_update messages are expected.

Node Discovery

To support node discovery, peers exchange node_announcement messages, which supply additional information about the nodes. There may be multiple node_announcement messages, in order to update the node information.

Resources

BOLT #7

References

[1] https://github.com/lightningnetwork/lightning-rfc/blob/master/07-routing-gossip.md