Inline [HK]
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of ext Jerry Ipe Thomas Sent: 15.January.2004 07:40 To: [EMAIL PROTECTED] Subject: [Sip-implementors] A few serious issues with RFC 3265! Importance: High Hi Guys! Let's consider the following scenario. UA_1: User Agent #1, the subscriber. UA_2: User Agent #2, the notifier. PS : Proxy Server LS : Location Service. | | |UA_1| | PS | |UA_2| |1| | |---SUBSCRIBE-->| | | | |2| | |<---401/407----| | | | |3| | |---SUBSCRIBE-->| |---SUBSCRIBE-->| | |4| | |<-----401------| |<-----401------| | |5| | |---SUBSCRIBE-->| |---SUBSCRIBE-->| | |6| | |<-----202------| |<-----202------| | |7| | |<----NOTIFY----| |<----NOTIFY----| | |8| | |------200----->| |------200----->| | 1. UA_1 sends a SUBSCRIBE with Request URI, that of UA_2. 2. PS responds with a 401/407 saying "Authenticate with ME first!". 3. UA_1 sends SUBSCRIBE with credentials for PS's earlier challenge. PS now looks up in the LS and proxies the SUBSCRIBE to UA_2. 4. UA_2 responds with a 401 Unauthorised. How must one send credentials in the next SUBSCRIBE? i.e if we send credentials for PS, UA_2 will again reject the SUBSCRIBE. If we send credentials for UA_2, shouldn't PS reject it as it is a "new" request? What must one do? [HK] Send both. Another issue is whether a NOTIFY is re-transmitted at all. If UA_1 is busy doing something and cannot immediately respond to the NOTIFY or if it misses the NOTIFY, then what? Will UA_2 remove UA_1's subscription? [HK] Yes Also, problems occur when another dialog creating request is received. Let's consider two cases. 1. Say we receive a NOTIFY. In the next instant, we receive an INVITE. Now what? 2. Converse of 1 [HK] If you are talking about another dialog creating request arriving with the originally created dialog, then you create a new dialog association. This is all spelt out in RFC 3265. Regards, Jerry Ipe Thomas Trainee Engineer (R&D) D-Link India Software and R&D Center Bangalore Land Line: +91-80-6788350/51 Extn #: 117 _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
