SIP中对话和会话的区别？

Question

对话和会话之间到底有什么区别？ dialog 在信号意义上是否意味着 "call has already been setup"，而 session 在媒体意义上意味着 "media has already been setup"？

另外，"part of a dialog"是什么意思？是 "INVITE"、"ACK" 和考虑了回复 "part of a dialog"?

Answer 1

 Dialog: A dialog is a peer-to-peer SIP relationship between two

     UAs that persists for some time.  A dialog is established by
     SIP messages, such as a 2xx response to an INVITE request.  A
     dialog is identified by a call identifier, local tag, and a
     remote tag.  A dialog was formerly known as a call leg in RFC
     2543.

而

  Session: From the SDP specification: "A multimedia session is a

     set of multimedia senders and receivers and the data streams
     flowing from senders to receivers.  A multimedia conference is
     an example of a multimedia session." (RFC 2327 [1]) (A session
     as defined for SDP can comprise one or more RTP sessions.)  As
     defined, a callee can be invited several times, by different
     calls, to the same session.  If SDP is used, a session is
     defined by the concatenation of the SDP user name, session id,
     network type, address type, and address elements in the origin
     field.

用我自己的话来说：SIP 对话指的是两个对等点之间的信令关系。 SIP 对话可用于建立呼叫 (INVITE)，但还有其他 SIP 方法可以建立对话（例如 SUBSCRIBE）

使用 SDP offer/answer（参见 RFC 3264）

通过由 INVITE 方法启动的 SIP 对话交换（多媒体）会话

SIP中对话和会话的区别？

Difference between dialog and session in SIP?

session

dialog

sip