Hi Alex, thanks for the answer.
My customer is on the SIP side. So my customer sees a prefix of my PSTN gateway in the contact header. Sequential requests are being sent to <prefix><number>@<gateway_ip>. However I think when I remove the prefix from the contact, the gateway would have no problem in responding to this seq. request (Isn't the call defined by to_tag, from_tag, call_id?). So I want to hide the contact prefix from the UA. Efelin 2012/2/17 Alex Balashov <abalas...@evaristesys.com>: > Efelin, > > There is probably some confusion here. The 200 OK message is from your > gateway (in your call flow), and it can put whatever it wants in the Contact > URI; you have no control over that on the Kamailio side. You might be able > to influence it with configuration settings on the GW side, but most likely > not. > > However, much more importantly: the contact URI in the replies from the > gateway only serves to target your UA's sequential requests. It has nothing > to do with the other side of your GW. If it's a SIP -> TDM or analog GW, > then SIP details are totally irrelevant. If it's a SIP-to-SIP media gateway, > it's a back-to-back user agent, meaning it generates a whole new logical call > leg on the other side and bridges it to the incoming one from the UA. The > parameters in that new leg are completely independent of any attributes of > the old one. > > Regardless, the contact URI is something sent back to the UA to tell it how > to communicate with the GW. In the overall scheme of your call flow, no > matter the media, it is a "purely internal" attribute. > > -- > This message was painstakingly thumbed out on my mobile, so apologies for > brevity and errors. > > Alex Balashov - Principal > Evariste Systems LLC > 260 Peachtree Street NW > Suite 2200 > Atlanta, GA 30303 > Tel: +1-678-954-0670 > Fax: +1-404-961-1892 > Web: http://www.evaristesys.com/, http://www.alexbalashov.com > > On Feb 17, 2012, at 9:20 AM, Efelin Novak <efelin.no...@gmail.com> wrote: > >> Hi folks, >> >> I have a topology like this: >> >> UA -> kamailio -> PSTN GW. >> >> When I'm placing calls to a PSTN I have to append prefixes so the PSTN >> GW knows how to route the call. So the request-uri is >> <prefix><number>@<gateway_ip> e.g. 999123456@192.168.1.1. When the UA >> calls to the GW a "200 OK" message contains a contact header with >> 999123456@192.168.1.1. This is a problem because I don't want my >> customers to see gateway prefixes. >> >> The Topoh module only hides IP addresses or the domain part. Is there >> any way to remove prefixes. This document >> (http://www.kamailio.org/events/2011-Cluecon/DCM-kamailio-security.pdf) >> stated "encoding IP and prefixes can be set via parameters". Can I >> remove prefixes from the contact in any other way than some contact >> header substitutions? >> >> Thanks >> >> Efelin >> >> _______________________________________________ >> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list >> sr-users@lists.sip-router.org >> http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users > > _______________________________________________ > SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list > sr-users@lists.sip-router.org > http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users _______________________________________________ SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list sr-users@lists.sip-router.org http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
