Session Initiation Protocol

aliases:

Application protocol that manages VoIP and conferencing communications.

SIP is responsible for managing user discovery, availability advertising, negotiating session parameters, session management and session termination. SIP endpoints are the end user devices, like IP-enabled handset or video-conferencing software.

SIP runs on 5060/tcp, 5060/udp, and 5061/tcp for TLS-based encryption.

Each device, conference, or telephony user is assigned a unique SIP address called an SIP URI.

sip:table@liltable.dev
sip:2393773300@collierschools.com
meet:sip:organizer@organization.org;ms-app=conf;ms-conf-id=subg42
tel:+12393773300

The tel: URI scheme allows SIP endpoints to dial a landline or cell phone. It either follows the global E.164 telephone number format or the local format (for internal extensions).

While SIP provides session management, the delivery of realtime data is managed by other protocols, like RTP and ~~RTCP.~~RTCP.