Definitions for Network Elements
From PBXes
Service Provider SIP-Signaling Entity (SP-SSE) – the Service Provider’s point of SIP signaling interconnection with the Enterprise.
SIP-PBX – the Enterprise’s point of SIP signaling interconnection with the Service Provider.
SIP Endpoint – a term used in this specification to refer to both SP-SSEs and SIP-PBXes.
Enterprise Public Identity - an Address of Record (AOR) represented as a SIP URI, used to identify a user or group of users served by the SIP-PBX. Enterprise Public Identities are used in conjunction with delivering incoming and outgoing calls.
Registration AOR – An AOR represented as a SIP URI, used solely to identify the SIP-PBX during registration.
Media Endpoint – Any entity that terminates an RTP/RTCP stream.
Back-to-Back User Agent (B2BUA) –a logical entity that receives a request and processes it as a user agent server (UAS). In order to determine how the request should be answered, it acts as a user agent client (UAC) and generates a request to another SIP user agent server (UAS).