Dear List,This is a big explanation with enough information except ngrep/ethereal captures, in both cases :ADSL Connection Speed : 512/128,ATA's : Zyxel P2002,Codec : G729,RTP Port Range : 19000-20000,and OpenSER on Public IP without NAT etc.I think i should change the ser.cfg to use MediaProxy just for SIP2SIP calls not for PSTN calls and i do not know how to do it, any clues ?Thanks,Ozan* A Side client use Zoom 4X, port forwarding to ATA in modem setting i register as port:5060 (openserctl ul show),* B Side client use Zyxel 660R, port forwarding to ATA in modem setting and register as port:10XXX (openserctl ul show),* Make a call to other sip client it's okay voice quality is acceptable most of time, but caller or callee losts ADSL connection after 30-60 seconds,* From A Side (Zoom 4X), make a call to PSTN, ADSL crashes, everything locks up,* From B Side (Zyxel 660R), make a call to PSTN, everything is normal, connection never down.ps: If i change A Side client modem to Zyxel 660R too as B Side client, the problems are totaly same.here is my basic ser.cfg >>>debug=3fork=yeslog_stderror=nocheck_via=nolisten=212.XXX.104.XXX # OpenSER Server on Public IP port=5060children=4dns=norev_dns=nofifo="/tmp/openser_fifo"loadmodule "/usr/local/lib/openser/modules/sl.so"loadmodule "/usr/local/lib/openser/modules/tm.so"loadmodule "/usr/local/lib/openser/modules/rr.so"loadmodule "/usr/local/lib/openser/modules/maxfwd.so"loadmodule "/usr/local/lib/openser/modules/usrloc.so"loadmodule "/usr/local/lib/openser/modules/registrar.so"modparam("usrloc", "db_mode", 0)modparam("rr", "enable_full_lr", 1)route { if (!mf_process_maxfwd_header("10")) { sl_send_reply("483", "Too Many Hops"); break; }; if (msg:len > max_len) { sl_send_reply("513", "Message Overflow"); break; }; if (method!="REGISTER") { record_route(); }; if (loose_route()) { route(1); break; }; if (uri!=myself) { route(1); break; }; if (uri==myself) { if (method=="REGISTER") { route(2); break; }; lookup("aliases"); if (uri!=myself) { route(1); break; }; if (uri=~"^sip:0[0-9]*@*") { rewritehost("195.XXX.122.XXX"); # PSTN Gateway on Public IP route(1); break; }; if (!lookup("location")) { sl_send_reply("404", "User Not Found"); break; }; route(1); };}route[1] { if (!t_relay()) { sl_reply_error(); };}route[2] { if (!save("location")) { sl_reply_error(); };}In my advanced SER.CFG ;* A Side client use Zoom 4X, port forwarding to ATA in modem setting i register as port:1XXXX (openserctl ul show),* B Side client use Zyxel 660R, port forwarding to ATA in modem setting and register as port:1XXXX (openserctl ul show),* Make a call to other sip client it's okay voice quality is worse then first case most of time, connection never down,* From A Side (Zoom 4X), make a call to PSTN, everything is normal, connection never down,* From B Side (Zyxel 660R), make a call to PSTN, everything is normal, connection never down.ps : If i change both A Side client and B Side client modems not to do port forwarding, problems are totaly same.here is my advanced ser.cfg >>>debug=3 fork=yes log_stderror=no listen=212.XXX.104.XXX # OpenSER Server on Public IP port=5060 children=4 alias=212.XXX.104.XXX # OpenSER Server on Public IP dns=no rev_dns=no fifo="/tmp/openser_fifo" fifo_db_url="mysql://openser:openserrw@localhost/openser" loadmodule "/usr/local/lib/openser/modules/mysql.so" loadmodule "/usr/local/lib/openser/modules/sl.so" loadmodule "/usr/local/lib/openser/modules/tm.so" loadmodule "/usr/local/lib/openser/modules/rr.so" loadmodule "/usr/local/lib/openser/modules/maxfwd.so" loadmodule "/usr/local/lib/openser/modules/usrloc.so" loadmodule "/usr/local/lib/openser/modules/registrar.so" loadmodule "/usr/local/lib/openser/modules/auth.so" loadmodule "/usr/local/lib/openser/modules/auth_db.so" loadmodule "/usr/local/lib/openser/modules/uri.so" loadmodule "/usr/local/lib/openser/modules/uri_db.so" loadmodule "/usr/local/lib/openser/modules/mediaproxy.so" loadmodule "/usr/local/lib/openser/modules/nathelper.so" loadmodule "/usr/local/lib/openser/modules/textops.so" loadmodule "/usr/local/lib/openser/modules/domain.so" loadmodule "/usr/local/lib/openser/modules/acc.so" modparam("auth_db", "calculate_ha1", 1) modparam("auth_db", "password_column", "password") modparam("auth_db", "use_domain", 1) modparam("domain", "db_mode", 1) modparam("nathelper", "rtpproxy_disable", 1) modparam("nathelper", "natping_interval", 180) modparam("mediaproxy","natping_interval", 30) modparam("mediaproxy","mediaproxy_socket", "/var/run/mediaproxy.sock") modparam("mediaproxy","sip_asymmetrics","/usr/local/etc/openser/sip-asymmetric-clients") modparam("mediaproxy","rtp_asymmetrics","/usr/local/etc/openser/rtp-asymmetric-clients") modparam("usrloc", "db_mode", 2) modparam("usrloc", "use_domain", 1) modparam("registrar", "default_expires", 60) modparam("registrar", "min_expires", 30) modparam("registrar", "nat_flag", 6) modparam("registrar", "use_domain", 1) modparam("rr", "enable_full_lr", 1) modparam("acc", "db_url", "mysql://openser:openserrw@localhost/openser") modparam("acc", "failed_transactions", 1) modparam("acc", "log_level", 1) modparam("acc", "log_flag", 1) modparam("acc", "db_flag", 1) route { # ----------------------------------------------------------------- # Sanity Check Section # ----------------------------------------------------------------- if (!mf_process_maxfwd_header("10")) { sl_send_reply("483", "Too Many Hops"); break; }; if (msg:len > max_len) { sl_send_reply("513", "Message Overflow"); break; }; # ----------------------------------------------------------------- # Record Route Section and Acc section # ----------------------------------------------------------------- if (method=="INVITE" && client_nat_test("3")) { record_route_preset("212.XXX.104.XXX:5060;nat=yes"); } else if (method!="REGISTER") { if!(uri=~"^sip:833[0-9]*@") { record_route(); setflag(1); } }; # ----------------------------------------------------------------- # Call Tear Down Section # ----------------------------------------------------------------- if (method=="BYE" || method=="CANCEL") { end_media_session(); }; # ----------------------------------------------------------------- # Loose Route Section # ----------------------------------------------------------------- if (loose_route()) { if (has_totag() && (method=="INVITE" || method=="ACK")) { if (client_nat_test("3") || search("^Route:.*;nat=yes")) { setflag(6); use_media_proxy(); }; }; route(1); break; }; # ----------------------------------------------------------------- # Call Type Processing Section # ----------------------------------------------------------------- if (uri!=myself) { route(1); break; }; if (uri==myself) { if (method=="CANCEL") { route(3); break; } else if (method=="INVITE") { route(3); break; } else if (method=="REGISTER") { route(2); break; }; lookup("aliases"); if (uri!=myself) { route(1); break; }; if (!lookup("location")) { sl_send_reply("404", "User Not Found"); break; }; }; route(1); } route[1] { # ----------------------------------------------------------------- # Default Message Handler # ----------------------------------------------------------------- t_on_reply("1"); if (!t_relay()) { if (method=="INVITE" || method=="ACK") { end_media_session(); }; sl_reply_error(); }; } route[2] { # ----------------------------------------------------------------- # REGISTER Message Handler # ---------------------------------------------------------------- if (!search("^Contact:\ +\*") && client_nat_test("7")) { setflag(6); fix_nated_register(); force_rport(); }; sl_send_reply("100", "Trying"); if (!www_authorize("","subscriber")) { www_challenge("","0"); break; }; if (!check_to()) { sl_send_reply("401", "Unauthorized"); break; }; consume_credentials(); if (!save("location")) { sl_reply_error(); }; } route[3] { # ----------------------------------------------------------------- # CANCEL and INVITE Message Handler # ----------------------------------------------------------------- if (client_nat_test("3")) { setflag(7); force_rport(); fix_nated_contact(); }; lookup("aliases"); if (uri!=myself) { route(1); break; }; if (uri=~"^sip:0[0-9]*@*") { rewritehost("195.XXX.122.XXX"); # PSTN Gateway on Public IP route(1); break; }; if (!lookup("location")) { sl_send_reply("404", "User Not Found"); break; }; if (method=="CANCEL") { route(1); break; }; if (!proxy_authorize("","subscriber")) { proxy_challenge("","0"); break; } else if (!check_from()) { sl_send_reply("403", "Use From=ID"); break; }; consume_credentials(); if (isflagset(6) || isflagset(7)) { use_media_proxy(); }; route(1); } onreply_route[1] { if ((isflagset(6) || isflagset(7)) && (status=~"(180)|(183)|2[0-9][0-9]")) { if (!search("^Content-Length:\ +0")) { use_media_proxy(); }; }; if (client_nat_test("1")) { fix_nated_contact(); }; }