It seems to me that you don't think a proxy can ever initiate any responses but, of course, sometimes it must. For example, if it received Max-Forwards:0 in a request, it must respond with a 483 Too Many Hops response. In such cases the proxy behaves like a UAS.
>From RFC3261... Being a proxy is a logical role for a SIP element. When a request arrives, an element that can play the role of a proxy first decides if it needs to respond to the request on its own. For instance, the request may be malformed or the element may need credentials from the client before acting as a proxy. The element MAY respond with any appropriate error code. When responding directly to a request, the element is playing the role of a UAS and MUST behave as described in Section 8.2. But once the request has been forwarded to the next hop, the proxy mustn't generate any responses itself because any responses will come from the next hop. Regards, Attila -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Adarsh Guler Sent: 16 March 2007 06:18 To: [email protected] Subject: [Sip-implementors] Stateless Proxy. HI, Can a Stateless Proxy initiate CANCEL after forwarding INVITE ...??? UAC send INVITE to a stateless Proxy, this proxy does Location service to get the next hop, but it could not get the next hop from Location Service. Then proxy should initiate4xx Reponse. But how does a stateless proxy initiate Response ..??? Thanks & Regards Adarsh S Guler ============================================================================================================================ Tech Mahindra, formerly Mahindra-British Telecom. Disclaimer: This message and the information contained herein is proprietary and confidential and subject to the Tech Mahindra policy statement, you may review at <a href="http://www.techmahindra.com/Disclaimer.html";>http://www.techmahindra.com/Disclaimer.html</a> externally and <a href="http://tim.techmahindra.com/Disclaimer.html";>http://tim.techmahindra.com/Disclaimer.html</a> internally within Tech Mahindra. ============================================================================================================================ _______________________________________________ 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
