Hello Mojtaba, Thanks for your reply. You are completely correct, my current configuration work fine when request initiated from UEs, but I want to handle SIP requests that initiated by application server. When UE sends request to S-CSCF, kamailio fetch iFC from HSS and check if the request match with iFC or not, if it matched kamailio forward the request to the application server. But when application server send request to S-CSCF, isc_from_as('orig') return false and I couldn't forward request to the target UE. Regards, Ali On Wed, Jul 24, 2019 at 3:45 PM Mojtaba <mespio(a)gmail.com> wrote:

Hello Ali, I think we had the similar problem. Then we found the S-CSCF configuration file contains following snippet in main routing block: if (($route_uri =~ "sip:orig@.*") || isc_from_as("orig")) { xlog("Orig"); # we need something like this to assign SCSCF to unregistered user for services # support for AS origination on behalf of unregistered useri # can use the registrar is_registered methods - must see if we need to check orig or term? # Originating route(orig); break; } else { And we understood, if the AS originates an initial Request (as opposed to forwarding it), then the S-CSCF should act as an originating S-CSCF, too. So the AS that performs an “originating, unregistered” service, must add a “Route” header with the indication of origin, e.g. Route: <sip:orig@172.23.12.249:5060;lr> To address the originating S-CSCF. Just my two cent. KR, Christoph From: sr-users &lt;sr-users-bounces(a)lists.kamailio.org&gt; On Behalf Of Ali Shirvani Sent: Wednesday, July 24, 2019 2:49 PM To: Kamailio (SER) - Development Mailing List &lt;sr-dev(a)lists.kamailio.org&gt; Cc: Kamailio (SER) - Users Mailing List &lt;sr-users(a)lists.kamailio.org&gt; Subject: Re: [SR-Users] [sr-dev] IMS_ISC technical specification Hello Mojtaba, Thanks for your reply. You are completely correct, my current configuration work fine when request initiated from UEs, but I want to handle SIP requests that initiated by application server. When UE sends request to S-CSCF, kamailio fetch iFC from HSS and check if the request match with iFC or not, if it matched kamailio forward the request to the application server. But when application server send request to S-CSCF, isc_from_as('orig') return false and I couldn't forward request to the target UE. Regards, Ali On Wed, Jul 24, 2019 at 3:45 PM Mojtaba <mespio@gmail.com<mailto:mespio@gmail.com>> wrote: Hello Ali, The SCSCF has IFC service for decision what it should do with incoming SIP message. During check all rules in IFC, If it match with one or some rules, actually it marked with that rules. Then the real meaning of marking is the SIP message is matched with one or some rules in IFC. With Best Regards. On Wed, Jul 24, 2019 at 2:48 PM Ali Shirvani <aj.shirvani@gmail.com<mailto:aj.shirvani@gmail.com>> wrote: Hi all, I read some portion of imc_isc_mod.c, specially isc_from_as function. In that function there is some function call that searching for some marks in the SIP message. Also I read section 5.7.3 from TS 24.229 but I didn't find the marking mechanism that used in isc_from_as function. Would you please point me to the technical specification that implemented in IMS_ISC module? Regards, Ali _______________________________________________ Kamailio (SER) - Development Mailing List sr-dev@lists.kamailio.org<mailto:sr-dev@lists.kamailio.org> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-dev -- --Mojtaba Esfandiari.S _______________________________________________ Kamailio (SER) - Development Mailing List sr-dev@lists.kamailio.org<mailto:sr-dev@lists.kamailio.org> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-dev The information contained in this e-mail message is privileged and confidential and is for the exclusive use of the addressee. The person who receives this message and who is not the addressee, one of his employees or an agent entitled to hand it over to the addressee, is informed that he may not use, disclose or reproduce the contents thereof, and is kindly asked to notify the sender and delete the e-mail immediately.