[Sip-implementors] Use of INFO before sending ACK

[Sarju Garg]

Hi all,   If the user sends a message that is not expected during the call state ,then how should UA behave to this message? FOr example if the calling side UA sends INFO while the call is being established (UA sends INVITE and then INFO without waiting to send ACK first), then how the does called side UA interpret this INFO message.  There are 3 possibilites: 1. Ignore it, will be retransmitted after sometime 2. Save it, send 1xx message and process it after receiving ACK 3. Send 409 message saying that this message is received at wrong time.   To me, 2 seems to be the right option. Please let me know which would be the correct behavior.   Thanks Sarju