Comments
ACK contains the media information If the media information contained in the ACK is not acceptable, then the called party must send a BYE to cancel the session-a CANCEL cannot be sent because the session is already established. A media session is considered established when the INVITE, 200 OK, and ACK messages have been exchanged. A successful INVITE request establishes a dialog between the two user agents, which continues until a BYE is sent by either party to end the session
Posted by HamidAliKhan
If an INVITE does not contain media information, the ACK contains the media information If the media information contained in the ACK is not acceptable, then the called party must send a BYE to cancel the session-a CANCEL cannot be sent because the session is already established. A media session is considered established when the INVITE, 200 OK, and ACK messages have been exchanged. A successful INVITE request establishes a dialog between the two user agents, which continues until a BYE is sent by either party to end the session
Posted by linux
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