In Part 1 of our SIP primer, I covered the SIP foundation layers starting from the message structure and ending with the SIP transactions. We saw how phone registrations and proxies could work using ...

SIP session requests leverage the “session description protocol (SDP)” to define session characteristics such as media type, codec, and so on. While the IETF and SIPforum have standardized many of the ...

Session Initiation Protocol (SIP) is a signaling protocol that is used to set up, modify, and terminate a session between two endpoints. SIP can be used to set up a two-party call, a multi-party call, ...

Session initiation protocol (SIP)-based voice-over-IP (VoIP) designs certainly provide some interesting benefits over today's Class 5 switching systems. SIP enables capabilities like presence, instant ...

Session Initiation Protocol (SIP) is a control (signaling) protocol developed by the Internet Engineering Task Force (IETF) to manage interactive multimedia IP sessions including IP telephony, ...

Broadcasting over IP is rapidly becoming the paradigm by which broadcasters are planning future broadcast network infrastructures. Within the diverse range of broadcast IP devices coming onto the ...

Session Initiation Protocol Recording, or SIPREC for short, defines the architecture, associated call flows, and metadata that can be used for call recording. "This call may be recorded for quality ...

Update: We're in the last throes of winter break 2019, which means most Ars' home office phones can stay dormant for a few more days. As such, we've been resurfacing a few classics from the ...