Yes. Generally, transactions can nest and overlap. For example PRACK transaction occurs completely within an INVITE transaction. Also other transactions can be initiated even before final response is received for the previous transaction.
But not all transactions may occur independently. For example, a new offer must not be made when a previous offer is not yet answered. But this is a restriction imposed by offer/answer model and not by SIP as such. Also checkout this RFC (Multiple dialog usages in SIP) http://www.ietf.org/rfc/rfc5057.txt -- Pandu On Wed, Jul 9, 2008 at 9:40 AM, Srivastava, Vimal < [EMAIL PROTECTED]> wrote: > > > > > ________________________________ > > From: Srivastava, Vimal > Sent: Wednesday, July 09, 2008 9:35 AM > To: '[email protected]' > Subject: 2 open transaction in the same call/dialog > > > > Hi All, > > > > Is it possible that in the same dialog or call, two open transactions > exists. > > e.g. > > > > Dialog is established and now the UAC sends INFO and before it gets > final response for INFO, it sends UPDATE also. > > > > Thanks > > Vimal > > > "This email message and any attachments are confidential information of > Starent Networks, Corp. The information transmitted may not be used to > create or change any contractual obligations of Starent Networks, Corp. Any > review, retransmission, dissemination or other use of, or taking of any > action in reliance upon this e-mail and its attachments by persons or > entities other than the intended recipient is prohibited. If you are not the > intended recipient, please notify the sender immediately -- by replying to > this message or by sending an email to [EMAIL PROTECTED] -- > and destroy all copies of this message and any attachments without reading > or disclosing their contents. Thank you." > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
