[SIPForum-discussion] SIP Sessions and SIP Dialog

[Dale R. Worley]

"Jason Morrison" <jason.voipengineer at gmail.com> writes:
> 1) SIP Dialog - Is a completed request with Call-ID, To and From Tags
> established which may or may not consist of a media stream
>
> 2) SIP Session - Is a SIP dialog that consisting of a media stream.

A "dialog" is a thing defined by SIP.  On the wire, it consists of
messages and responses.  They carry SDP, which describes the "session".

A "session" is a thing defined by SDP.  On the wire, it consists of RTP
and RTCP packets.

Thus a dialog and a session are associated with each other, but strictly
speaking, neither "consists of" the other.

Dale