Session Initiation Protocol (SIP)
Definition - What does Session Initiation Protocol (SIP) mean?
Session Initiation Protocol (SIP) is a text-based signaling protocol that establishes Internet Protocol (IP) network sessions at the application layer. Signaling protocols are used for signaling encapsulation identification.
SIP was designed in 1996 and approved by the Internet Engineering Task Force (IETF). RFC 3261 is the most current version.
Techopedia explains Session Initiation Protocol (SIP)
SIP is used in applications ranging from Unicast Voice Over Internet Protocol (VoIP) calls to multistream or multimedia conferencing. SIP runs on User Datagram Protocol (UDP), Stream Control Transmission Protocol (SCTP) or Transmission Control Protocol (TCP).
SIP was accepted as a 3rd Generation Partnership Project (3GPP) signaling protocol in November 2000 and became a permanent component of IP Multimedia Subsystem (IMS), which is a mobile (cellular) multimedia streaming framework.