Thanks for your quick response. I think this scenario is useful in cases where all the digits are not known and the INVITE is sent. Additional digits can be send in INFO message. But if I am building a UA for an end terminal user, then it should not receive INFO in such cases. What do you say in this case? How should I take in my UA call model?
- sarju ----- Original Message ----- From: Christer Holmberg <[EMAIL PROTECTED]> To: Sarju Garg <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Monday, November 12, 2001 2:16 PM Subject: Re: [Sip-implementors] Use of INFO before sending ACK > > Hi, > > There was a discussion on this some time ago, and the general > understanding is that it IS allowed to send INFO before the UAC has > received the 200 OK response and sent the ACK. > > However, unless the UAC has received a 18x provisional response, with a > To header tag and Contact header to use in the INFO, it can NOT assume > that proxis will handle/route an INFO in the same way as the INVITE. For > this reason it may (depending on the scenario you want to use INFO for) > be better if the UAS sends a 18x provisional response, instead of 100 > Trying, when it receives the INVITE, to make sure the UAC gets the To > tag and Contact header as soon as possible. They are also needed if the > UAC wants to terminate the specific call setup leg using BYE. > > Regards, > > Christer Holmberg > Ericsson Finland > > > Sarju Garg wrote: > > > > 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 > _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
