Probably a user agent that is actually an endpoint, like a PBX or media server. You should take a look at Asterisk or Freeswitch.

-- Alex Balashov - Principal Evariste Systems LLC 235 E Ponce de Leon Ave Suite 106 Atlanta, GA 30030 Tel: +1-678-954-0670 Fax: +1-404-961-1892 Web: http://www.evaristesys.com/, http://www.alexbalashov.com "Fomitchev, AndreiX" &lt;andreix.fomitchev(a)intel.com&gt; wrote: Hi Alex, Thank you for your response. Please, could you tell me what I need to setup a SIP "echo service"? I am new in SIP domain :/ Regards, *From:*sr-users-bounces@lists.sip-router.org [mailto:sr-users-bounces@lists.sip-router.org] *On Behalf Of *Alex Balashov *Sent:* Thursday, March 29, 2012 1:38 PM *To:* SIP Router - Kamailio (OpenSER) and SIP Express Router (SER) - Users Mailing List *Subject:* Re: [SR-Users] how to configure Kamailio in ECHO mode No, it&apos;s not possible. I think you have the wrong idea about what Kamailio is. Kamailio neither receives nor produces audio at all. -- Alex Balashov - Principal Evariste Systems LLC 235 E Ponce de Leon Ave Suite 106 Atlanta, GA 30030 Tel: +1-678-954-0670 Fax: +1-404-961-1892 Web: http://www.evaristesys.com/, http://www.alexbalashov.com "Fomitchev, AndreiX" &lt;andreix.fomitchev(a)intel.com <mailto:andreix.fomitchev@intel.com>> wrote: Oups, sorry, bad manipulation: I want to configure Kamailio in echo mode, i.e. SIP server repeats the input audio into the output, so I can hear myself with a very small amount of delay... Is it possible? If so, how? Thank you for your help. Best regards, *From:*Fomitchev, AndreiX *Sent:* Thursday, March 29, 2012 1:34 PM *To:* &#39;sr-users(a)lists.sip-router.org&#39; *Subject:* how to configure Kamailio in ECHO mode Hi, For testing purpose, I want to configure a Kamailio server in ECHO mode, i.e. SIP server --------------------------------------------------------------------- Intel Corporation SAS (French simplified joint stock company) Registered headquarters: "Les Montalets"- 2, rue de Paris, 92196 Meudon Cedex, France Registration Number: 302 456 199 R.C.S. NANTERRE Capital: 4,572,000 Euros This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. --------------------------------------------------------------------- Intel Corporation SAS (French simplified joint stock company) Registered headquarters: "Les Montalets"- 2, rue de Paris, 92196 Meudon Cedex, France Registration Number: 302 456 199 R.C.S. NANTERRE Capital: 4,572,000 Euros This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. _______________________________________________ SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list sr-users(a)lists.sip-router.org http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users