The Link-Local Messaging protocol is specified in XEP-0174 (a Final Standard of the XMPP Standards Foundation). This specification defines how to establish XMPP-like communications over local networks based on zero-configuration networking. This method uses DNS-based Service Discovery and Multicast DNS to discover entities that support the protocol, including their IP addresses and preferred ports. Any two entities can then negotiate a serverless connection using standard XML streams in order to exchange XMPP message and IQ stanzas.
Information about this XMPP protocol is maintained by the XMPP Registrar.