--- title: "Kamailio as SBC for MS Teams" date: 2023-06-25T09:11:44-05:00 draft: false --- Este post complementa con un ejemplo mínimo pero funcional de lo expuesto en [Kamailio as SBC for MS Teams](https://skalatan.de/en/blog/kamailio-sbc-teams). Escenario confirmado. ```mermaid flowchart LR MSTeams["MS Teams v.2023.6.21.5 "] Kamailio["Kamailio v5.4.4 RTPEngine 11.3.1.4 "] PBX["FreeSWITCH v1.10.9 "] MSTeams ---|TLS/PUBLIC IP| Kamailio Kamailio ---|UDP/PUBLIC IP| PBX ``` Funcionalidades confirmadas: * [X] Llamadas MSTeams a PBX * [X] Llamadas PBX a MSTeams * [X] MSTeams Hold * [X] MSTeams Park * [X] MSTeams Unpark Para que esta configuracion sea efectiva debes conectar [Kamailio a MS Teams](https://skalatan.de/en/blog/kamailio-sbc-teams) y una vez confirmes que MS Teams detecta el Kamailio puedes proceder a usar la configuracion entregada. **kamailio/kamailio.cfg** ```kamailio @mdtoapp file:kamailio/kamailio.cfg #!KAMAILIO # # Asesorias y Consultorias a contacto@bit4bit.in # ACTUALIZAR LOS VALORES A CONTINUACION #!substdef "!SIPS_PORT!7062!g" #!substdef "!SIP_PORT!5073!g" #!substdef "!PBX_IP!3.3.3.3!g" #!substdef "!PBX_SIP_PORT!5060!g" #!substdef "!EXTERNAL_IP!2.2.2.2!g" #!substdef "!EXTERNAL_FQDN!demo.bit4bit.in!g" debug=2 log_stderror=no log_facility=LOG_LOCAL0 log_prefix="{$mt $hdr(CSeq) $ci} " children=8 alias=EXTERNAL_FQDN:SIPS_PORT alias=EXTERNAL_FQDN:SIP_PORT listen=tls:EXTERNAL_IP:SIPS_PORT advertise EXTERNAL_FQDN:SIPS_PORT listen=udp:EXTERNAL_IP:SIP_PORT advertise EXTERNAL_FQDN:SIP_PORT enable_tls=yes tls_max_connections=2048 enable_sctp=no loadmodule "kex.so" loadmodule "corex.so" loadmodule "tm.so" loadmodule "tmx.so" loadmodule "sl.so" loadmodule "rr.so" loadmodule "pv.so" loadmodule "maxfwd.so" loadmodule "textops.so" loadmodule "textopsx.so" loadmodule "siputils.so" loadmodule "xlog.so" loadmodule "ctl.so" loadmodule "dispatcher.so" loadmodule "rtpengine.so" loadmodule "nathelper.so" loadmodule "tls.so" modparam("rtpengine", "rtpengine_sock", "udp:127.0.0.1:2223") modparam("tls", "config", "/etc/kamailio/tls.cfg") modparam("dispatcher", "list_file", "/etc/kamailio/dispatcher.list") modparam("dispatcher", "ds_probing_mode", 1) modparam("dispatcher", "ds_ping_interval", 10) ####### Routing Logic ######## request_route { if (!mf_process_maxfwd_header("10")) { sl_send_reply("483","Too Many Hops"); exit; } if(is_method("OPTIONS") && uri==myself && $rU==$null) { sl_send_reply("200","Keepalive"); exit; } # FROM MSTEAMS if($hdr(User-Agent) =~ "Microsoft.PSTNHub") { $du = "sip:PBX_IP:PBX_SIP_PORT;transport=udp"; } # TO MSTEAMS else { $du = "sip:sip.pstnhub.microsoft.com;transport=tls"; } if ($rU==$null) { sl_send_reply("484","Address Incomplete"); exit; } record_route(); route(RELAY); } route[RELAY] { route(REFER); if (is_method("INVITE|BYE|CANCEL")) { if(!t_is_set("branch_route")) t_on_branch("MANAGE_BRANCH"); } if (is_method("INVITE")) { if(!t_is_set("onreply_route")) t_on_reply("MANAGE_REPLY"); } if (!t_relay()) { sl_reply_error(); } exit; } route[RTPMANAGE] { if (!has_body("application/sdp")) { return; } if($dd =~ "sip.pstnhub.microsoft.com") { rtpengine_offer("trust-address replace-origin replace-session-connection ICE=force transcode-PCMU transcode-G722 RTP/SAVP"); } else { rtpengine_answer("trust-address replace-origin replace-session-connection ICE=remove RTP/AVP"); } return; } route[RTPREPLY] { if (!has_body("application/sdp")) { return; } if ($fd == "PBX_IP") { rtpengine_offer("trust-address replace-origin replace-session-connection ICE=remove RTP/AVP"); } else { rtpengine_answer("trust-address replace-origin replace-session-connection ICE=force transcode-PCMU transcode-G722 RTP/SAVP"); } return; } route[REFER] { exclude_hf_value("Allow", "REFER"); return; } branch_route[MANAGE_BRANCH] { route(RTPMANAGE); } onreply_route[MANAGE_REPLY] { route(REFER); if(status=~"[12][0-9][0-9]") { route(RTPREPLY); } } event_route[tm:local-request] { if (is_method("OPTIONS") && $ru =~ "pstnhub.microsoft.com") { append_hf("Contact: \r\n"); } } ``` **kamailio/tls.cfg** ```kamailio @mdtoapp file:kamailio/tls.cfg [server:default] method = TLSv1.2+ verify_certificate = no require_certificate = no private_key = HERE YOUR PRIVATE KEY certificate = HERE YOUR CERTIFICATE [client:default] method = TLSv1.2+ verify_certificate = no require_certificate = no private_key = HERE YOUR PRIVATE KEY certificate = HERE YOUR CERTIFICATE ``` **kamailio/dispatcher.list** ```csv @mdtoapp file:kamailio/dispatcher.list # setid(integer) destination(sip uri) flags (integer, optional), priority(int,opt), attrs (str,optional) 1 sip:sip.pstnhub.microsoft.com;transport=tls 0 3 socket=tls:HERE EXTERNAL IP:HERE SIPS PORT;ping_from=sip:HERE EXTERNAL FQDN 1 sip:sip2.pstnhub.microsoft.com;transport=tls 0 2 socket=tls:HERE EXTERNAL IP:HERE SIPS PORT;ping_from=sip:HERE EXTERNAL FQDN 1 sip:sip3.pstnhub.microsoft.com;transport=tls 0 1 socket=tls:HERE EXTERNAL IP:HERE SIPS PORT;ping_from=sip:HERE EXTERNAL FQDN ``` Para escenarios más complejos o funcionalidades no presentes puedes contactarme a [contacto@bit4bit.in](mailto:contacto@bit4bit.in). ## Referencias - [Kamailio as SBC for MS Teams](https://skalatan.de/en/blog/kamailio-sbc-teams). - [DSIPRouter kamailio.cfg](https://github.com/dOpensource/dsiprouter/blob/master/kamailio/configs/kamailio.cfg)