SIP

Which layer is SIP? I thought it would be layer 5, "Session" (thought that was a give away) initiation Protocol. This site says it's level 7 application??? https://searchunifiedcommunications.techtarget.com/definition/Session-Initiation-Protocol Officially SIP is a layer 7 protocol. This comes from RFC 2543 which defines the SIP protocol. However, there does seem to be some confusion or differing opinions about this. Cisco has a document discussing their VoIP solution which says SIP works at layer 5. I would assume that the RFC would be the official source document for determining what layer SIP works at. https://www.ietf.org/rfc/rfc2543.txt -- RFC 2543 https://supportforums.cisco.com/document/12142746/understanding-transport-layer-sip-and-h323 Ok thanks for that :)