The point that I want to make is this - I think that end-to-end identity is important. John and Hadriel have pointed out problems with the methods available to attain end-to-end identity. This is an important issue to address. Those intermediary devices are not only there to address a SSP subscriber's policy for termination or origination services, but also for just plain interoperability.
Adam > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of > Elwell, John > Sent: Thursday, July 31, 2008 8:29 AM > To: Dean Willis; Uzelac, Adam > Cc: Cullen Jennings; SIP IETF > Subject: Re: [Sip] Thoughts on SIP Identity issues > > > > > -----Original Message----- > > From: Dean Willis [mailto:[EMAIL PROTECTED] > > Sent: 30 July 2008 17:23 > > To: Uzelac, Adam > > Cc: Cullen Jennings; Elwell, John; SIP IETF > > Subject: Re: [Sip] Thoughts on SIP Identity issues > > > > > > On Jul 30, 2008, at 12:05 PM, Uzelac, Adam wrote: > > > > > I believe that the problem statement (and associated use > > cases) that > > > John presented in the WG session are valid. I think it was > > > unfortunate that those use cases couldn't be discussed more in the > > > WG session. This email appears to me simply John trying to > > further > > > the discussions to bring out arguments. > > > > > > One particular note I would like to share - given a comment at the > > > mic regarding 4474 working as designed and desired - is that there > > > are situations (good, bad or indifferent) that necessitate changes > > > in the SDP. John cited media steering as a use case. Another use > > > case is media steering for transcoding. Use case below: > > > > > > Ent A--->SSP1--->Ent B > > > > > In this use case, Ent A and SSP1 have established certain > > "rules of > > > engagement", like G729, 2833, t.38, etc. Ent B and SSP1 have > > > established their own "rules of engagement", for instance G711 for > > > voice, inband DTMF/FAX, etc. Being there's no common denominator > > > for the media, the SDP in INVITE "steers" to a device that can > > > trancode. > > > > > > > This is more that sterring; the media is being terminated at > > a device > > that transcodes it. Then a new media stream flows out the other side. > > > > When media transcoding is occurring, media integrity is > > hop-by-hop. I > > maintain that we have no need for an end-to-end identity > > representation when the media itself is hop by hop. > > > > > > > Another use case, would be for those SSPs that have Lawful > > Intercept > > > requirements. Steering the media to something that will can > > > intercept should that be a regulatory obligation. > > > > > > Same as above. Although one should note that proper use of DTLS-SRTP > > to detect the lawful intercept. > [JRE] Media steering is sufficient to accomplish LI. The encrypted > stream is delivered to the authorities. The authorities need to go to > the end domain to be able to have access to the encryption key and/or > the unencrypted stream. An intermediate domain cannot be held > responsible for encryption done by end domains. > > John > _______________________________________________ > Sip mailing list https://www.ietf.org/mailman/listinfo/sip > This list is for NEW development of the core SIP Protocol > Use [EMAIL PROTECTED] for questions on current sip > Use [EMAIL PROTECTED] for new developments on the application of sip _______________________________________________ Sip mailing list https://www.ietf.org/mailman/listinfo/sip This list is for NEW development of the core SIP Protocol Use [EMAIL PROTECTED] for questions on current sip Use [EMAIL PROTECTED] for new developments on the application of sip
