RE: [Serusers] SER on masqueraded/NAT connection

I would suggest a cisco router to act as a NAT. it can read the SIP messages properly. Though I'm still undergoing some tests with it, so far sa good :) -----Original Message----- From: serusers-admin(a)iptel.org [mailto:serusers-admin@lists.iptel.org] On Behalf Of Jiri Kuthan Sent: Tuesday, January 14, 2003 9:46 PM To: Craig Graham; serusers(a)lists.iptel.org Subject: Re: [Serusers] SER on masqueraded/NAT connection Craigh, the problem unfortunately lives deeper than in SER -- it is about SIP interaction with NATs. SIP advertises IP addresses and port numbers in its messages, a technique which does not work along with NATs. What happens is that SIP messages from your private network get out to the public Internet, still carry private IP addresses in it, and attempts of other call parties to use these private IP addresses will fail. A preview of the .11 documentation mentions these issues. (I hope the correct link is www.iptel.org/ser/doc/, I'm offline now.) I'm unfortunately not aware of a method that would be able to traverse Linux-NAT for Messengers. All of the methods I'm aware of take some kind of NAT-support in end-devices, SIP-support in NATs or both. They include ALG (i.e., SIP awareness in NATs,for example intertex NATs do that), STUN (phones' ability to "fool" NATs, for example k-phone or snom do it), UPnP (must be supported by both phone and NAT), manual configuration (one must have "tweakable" phones and NATs and the ability to actually tweak both), or "symmetric phones" (like Cisco's ATA). -Jiri At 11:28 AM 1/14/2003, Craig Graham wrote: ports -> -> -- Jiri Kuthan http://iptel.org/~jiri/ _______________________________________________ Serusers mailing list serusers(a)lists.iptel.org http://lists.iptel.org/mailman/listinfo/serusers