On Thursday 17 January 2008 15:23:22 Paul Kyzivat wrote: > Iñaki Baz Castillo wrote: > > On Thursday 17 January 2008 14:08:07 Paul Kyzivat wrote: > >> Anybody that you permit to register with your scheme can still put any > >> ip it wants into the the contact addresses it registers. So you haven't > >> solved the problem you set out to solve. Having something special in the > >> user part doesn't change that. > > > > It would avoid fraudulent calls through gateways and call to any existing > > SIP account. Yes, the INVITE would arrive to the IP you set in "Contact" > > but it will be rejected since that URI doesn't exist. > > > > For example, nothing should occur if an INVITE like: > > INVITE sip:[EMAIL PROTECTED] > > arrives to the gateway. It would be rejected. > > This requires that every sip device in the universe adopt your naming > convention for Contact addresses. That isn't going to happen.
Yes, that's really true. Maybe this could be implemented locally (if devices allow setting "Contact" username). > >> Regarding your authentication example: if user2 does this, and the owner > >> of phone1 complains, then user2 can be punished. In any case, you can > >> modify your example so the contact used by user2 is: > >> <sip:[EMAIL PROTECTED]>. In that case the registrar will permit this > >> according to your proposal. > > > > Yes, but when the "INVITE sip:[EMAIL PROTECTED]" arrives to phone1 it will > > be rejected with 404. > > This is the same as in-dialog messages, proxies allow them and it's > > responsability of UAS to reject messages with a To tag not corresponding > > to an existing session. > > I'll also mention that it is quite common (though not especially wise) > for UAs to use the same contact address for registrations to multiple > AORs. And it is pretty common for specialized UAs, like phones, to > entirely ignore the R-URI and process any requests incoming to their sip > port. Ops, that a point I didn't consider. Thanks for explanations. -- ilimit... *Iñaki Baz Castillo* [EMAIL PROTECTED] ÀREA SISTEMES 0034 937 333 375 VOLTA 1, PIS 5 08224 TERRASSA.BCN Aquest enviament és confidencial i està destinat únicament a la persona a qui s'ha enviat. Pot contenir informació privada sotmesa al secret professional, la distribució de la qual està prohibida per la legislació vigent. _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
