9 feb 2010 kl. 21.35 skrev Dale Worley: > On Tue, 2010-02-09 at 09:24 +0100, Olle E. Johansson wrote: >> Isn't there an important difference to be noted here. In one call >> setup, you can have multiple 407 challenges, but only one 401. >> If you're using an outbound proxy, that proxy can challenge you, as >> well as the home proxy and the UA on the receiving end. > > Assuming that one does not use "Request-Disposition: no-cancel" and > there are no race conditions, the UAC can receive only one 4xx for each > INVITE it sends out. Successive re-sends of the INVITE may receive > multiple 407 responses, as different proxies may demand credentials for > different realms. (Although it's unlikely in practice that the UAC will > need credentials for more than one realm.) I said "call setup" - not "one attempt" :-)
It does happen that you get challenges in more than one realm, even though I admit it doesn't happen very often. In the web world, it's the case I described above with a web proxy challenging in one realm, and the end server in another. In the SIP world, the same situation could very well happen. To bypass the SBC, you need to authenticate for the SBC to authorize you to bypass it to your final destination. > Similarly, successive > re-sends of the INVITE could receive multiple 401 responses, if the > INVITEs go to different destinations that demand credentials for > different realms. Oh. That's evil. I new I could count on you to come up with something even more stressful than what I could imagine in my strange SIP mind. We need to remember that for next SIPit. ;-) /O _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
