That is an interesting, but nonstandard (and incorrect), registrar behavior. Are you actually encountering that somewhere?
If the UA wants a contact bound to its address as it appears on the other side of a NAT, it needs to use STUN to discover it and place it in the Contact in the Register request. RjS On Jun 21, 2007, at 9:07 PM, Richard wrote: > > Suppose UA1, which is behind NAT, is registering a public SIP server. > UA1 > (only necessary headers are shown) > REGISTER sip:serviceprovider.com > To: <sip:[EMAIL PROTECTED]> > From: <sip:[EMAIL PROTECTED]> > Contact: <sip:[EMAIL PROTECTED];expires=3600> > > Then UA1 receives the 200 OK response: > 200 OK > Contact: <sip:[EMAIL PROTECTED]:15060;expires=3600> > > Then UA2, which is located in other machine and is also behind NAT, > registers to the same public SIP server using the same AOR. > > REGISTER sip:serviceprovider.com > To: <sip:[EMAIL PROTECTED]> > From: <sip:[EMAIL PROTECTED]> > Contact: <sip:[EMAIL PROTECTED];expires=3600> > > Then UA2 receives the 200 OK response: > 200 OK > Contact: <sip:[EMAIL PROTECTED]:15060;expires=3500> > Contact: <sip:[EMAIL PROTECTED]:25060;expires=3600> > >> From UA2 point of view, it does not know which contact header it is > belong to. > > Another question is: would I use the contact header (with mapped > public > address) from the register 200 OK response to put in creating INVITE > message instead of consulting the STUN server if the UA is behind NAT? > > Richard > Senior Engineer > ASTRI > > > > This message (including any attachments) is for the named addressee > (s)'s use only. It may contain > sensitive, confidential, private proprietary or legally privileged > information intended for a > specific individual and purpose, and is protected by law. If you > are not the intended recipient, > please immediately delete it and all copies of it from your system, > destroy any hard copies of it > and notify the sender. Any use, disclosure, copying, or > distribution of this message and/or any > attachments is strictly prohibited. > > > _______________________________________________ > 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
