Moved to SIP implementors list... >From RFC 2543 bis 02 6.47.2 "If the sender��s address is incorrect, the proxy MUST add a ��received�� parameter to the Via header field inserted by the previous hop. Such a modified Via header field is known as a receiver-tagged Via header field. An example is: Via: SIP/2.0/UDP 10.0.0.1:5060 ;received=199.172.136.3 " The Via field is handled by the proxies in this way. And about the Registration process, the Registrar takes whatever value is there in the contact irrespective from where the request came. In this case the user will be registered with the address 128.1.1.1 . Please have a look at draft-rosenberg-sip-entfw-01 or draft-biggs-sip-nat- 00 or any other related draft for a detailed understanding of how SIP can be used with NATs and Firewalls. Cheers, Philips With limitless IMAGINATION, energetic ACTION and a deep sense of JOY!!! Philip T Jacob MindTree Consulting 91-80-6545266 -->-----Original Message----- -->From: [EMAIL PROTECTED] -->[mailto:[EMAIL PROTECTED]]On Behalf Of [EMAIL PROTECTED] -->Sent: Thursday, March 22, 2001 5:40 AM -->To: [EMAIL PROTECTED] -->Subject: [SIP] When the registra(or proxy) received a packet -->that topmost via header does not match received addr ? --> --> -->UAc send a REGISTER message via it's NAT box. --> -->this is UAc's REGISTER message --> -->REGISTER sip:210.221.183.29 SIP/2.0 -->Via: SIP/2.0/UDP 128.1.1.1:5060 -->From: jinho <sip:[EMAIL PROTECTED]> -->To: jinho <sip:[EMAIL PROTECTED]> -->Cseq: 1 REGISTER -->Call-ID: [EMAIL PROTECTED] -->Contact: jinho <sip:[EMAIL PROTECTED]> -->Content-Length: 0 -->Expires: 999999999 --> -->source ip address(NAT) : 222.154.182.25 --> -->At this time, --> what the registra(or proxy) server saves UAc's real address? --> -->222.154.182.25 or -->128.1.1.1 --> -->I think that it is 222.154.182.25 absolutely. How do yours -->think about that ? --> -->Best regards!!! --> --> _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
