Hallo,

ich habe in einen LANCOM Router 1781VA Rufnummer einer CPBX konfiguriert, der Internetanschluss läuft über einen Regio-Anschluss. Nach einem Neustart des Routers läuft alles in Ordnung, Rufe gehen rein und raus. Nach einer Zeit X erhält der Router bei abgehenden Rufen nur noch ein "403 Forbidden"?

[SIP-Packet] 2020/09/17 23:47:17,057  Devicetime: 2020/09/17 23:47:19,308 [Packet]: 
Sending datagram (2089 Bytes) from 212.110.197.66:15387 to 217.0.21.68:5061 using TLS (RtgTag 0):
INVITE sip:+4953319****5@tel.t-online.de SIP/2.0\r\n
Via: SIP/2.0/TLS 212.110.197.66:15387;branch=z9hG4bK-5968722d-e03f9895;rport\r\n
From: <sip:+4953316***9001@tel.t-online.de;user=phone>;tag=-955557620-577905825\r\n
To: <sip:+4953319****5@tel.t-online.de>\r\n
Call-ID: 842403725@00a0572bb1da\r\n
CSeq: 100 INVITE\r\n
Max-Forwards: 70\r\n
User-Agent: LANCOM 1781VA (over ISDN) / 10.32.0176 / 21.04.2020\r\n
Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, PRACK, REFER, NOTIFY, SUBSCRIBE, INFO\r\n
Supported: 100rel,timer\r\n
Contact: <sip:+4953316***9001@212.110.197.66:15387;transport=TLS>\r\n
P-Asserted-Identity: <sip:+4953316***9001@tel.t-online.de;user=phone>\r\n
Authorization: Digest username="*********@tel.t-online.de", realm="tel.t-online.de", algorithm=MD5, uri="sip:+4953319****5@tel.t-online.de", nonce="9B96273995CF635F00000000BA368C33",qop=auth, cnonce="7a51c273d0906219", nc=00000008, response="297f07d6abf16f9931ee23743bed9ba7"\r\n
Security-Verify: msrp-tls;mediasec\r\n
Security-Verify: sdes-srtp;mediasec\r\n
Security-Verify: dtls-srtp;mediasec\r\n
Content-Type: application/sdp\r\n
Content-Length: 1014\r\n
\r\n
v=0\r\n
o=- 4104357094 4104357094 IN IP4 212.110.197.66\r\n
s=call\r\n
c=IN IP4 212.110.197.66\r\n
t=0 0\r\n
m=audio 15246 RTP/SAVP 98 97 8 0 3 101\r\n
a=rtpmap:98 speex/16000\r\n
a=rtpmap:97 speex/8000\r\n
a=rtpmap:8 PCMA/8000\r\n
a=rtpmap:0 PCMU/8000\r\n
a=rtpmap:3 GSM/8000\r\n
a=rtpmap:101 telephone-event/8000\r\n
a=fmtp:101 0-15\r\n
a=crypto:100 AES_256_CM_HMAC_SHA1_80 inline:7flP5GNVw5DQsbDZ8ojV7+7ibSBhPmSMaFWf52SwC1IrJKa6GsOK25nzqxN34w==\r\n
a=crypto:101 AES_256_CM_HMAC_SHA1_32 inline:D+kddlcsCBJtmoIQyoK+0nU4y8UpGt0v43zrkVcmf1S14p6U2L0+eri52SYdcw==\r\n
a=crypto:102 AES_192_CM_HMAC_SHA1_80 inline:1fbE6YBRlOMGZdWUJLYuksswnLnibgsVsQOVOYzUmFPbu4ZoYNo=\r\n
a=crypto:103 AES_192_CM_HMAC_SHA1_32 inline:7ghMH04RuFQsoub3FJT7jxOQEG/a5/9rNyYDcxYALkRrvAPq6hg=\r\n
a=crypto:104 AES_CM_128_HMAC_SHA1_80 inline:1qknhlSyJ6P0c5bix+gqmW4pyO/I23mG2/2Yw0MI\r\n
a=crypto:105 AES_CM_128_HMAC_SHA1_32 inline:5t0gffmOuxTMspdJlRHw9rcSSp8Z0GhMdV1Axo7w\r\n
a=crypto:106 F8_128_HMAC_SHA1_80 inline:IbhBWina3GaLZSAhpi5Pmfw96Z5H9QCj2SU0LTl7\r\n
a=3ge2ae:requested\r\n
a=sendrecv\r\n
a=ptime:20\r\n


[SIP-Packet] 2020/09/17 23:47:17,108  Devicetime: 2020/09/17 23:47:19,359 [Packet]: 
Receiving datagram (371 Bytes) at 212.110.197.66:15387 from 217.0.21.68:5061 using TLS (RtgTag 0):
SIP/2.0 403 Forbidden\r\n
Via: SIP/2.0/TLS 212.110.197.66:15387;received=212.110.197.66;rport=15387;branch=z9hG4bK-5968722d-e03f9895\r\n
To: <sip:+4953319****5@tel.t-online.de>;tag=h7g4Esbg_i6bxqes6g1wjvbbw9etvo3c5jwfn7jyd\r\n
From: <sip:+4953316***9001@tel.t-online.de;user=phone>;tag=-955557620-577905825\r\n
Call-ID: 842403725@00a0572bb1da\r\n
CSeq: 100 INVITE\r\n
Content-Length: 0\r\n
\r\n

Die SIP-Registrierung läuft regelmäßig erfolgreich durch.

Was kann denn hier das Problem sein?

Warum liefert die CPBX ein "403 Forbidden"?

Nach einem neu Start bzw. de/aktivieren der SIP-Leitung im Router funktionieren die Rufe:

[SIP-Packet] 2020/09/17 23:57:03,678  Devicetime: 2020/09/17 23:57:05,963 [Packet]: 
Sending datagram (2099 Bytes) from 212.110.197.66:10466 to 217.0.21.68:5061 using TLS (RtgTag 0):
INVITE sip:+4953319****5@tel.t-online.de SIP/2.0\r\n
Via: SIP/2.0/TLS 212.110.197.66:10466;branch=z9hG4bK-f36961de-62314e2a;rport\r\n
From: <sip:+4953316***9001@tel.t-online.de;user=phone>;tag=-1947401466--1606031634\r\n
To: <sip:+4953319****5@tel.t-online.de>\r\n
Call-ID: 3740630087@00a0572bb1da\r\n
CSeq: 101 INVITE\r\n
Max-Forwards: 70\r\n
User-Agent: LANCOM 1781VA (over ISDN) / 10.32.0176 / 21.04.2020\r\n
Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, PRACK, REFER, NOTIFY, SUBSCRIBE, INFO\r\n
Supported: 100rel,timer\r\n
Proxy-Authorization: Digest username="*********@tel.t-online.de", realm="tel.t-online.de", algorithm=MD5, uri="sip:+4953319****5@tel.t-online.de", nonce="FEEF0412BADB635F000000008576F860",qop=auth, cnonce="2ef5137c177a89be", nc=00000001, response="9b924c2090a54666dd4020e941f820ed"\r\n
Security-Verify: msrp-tls;mediasec\r\n
Security-Verify: sdes-srtp;mediasec\r\n
Security-Verify: dtls-srtp;mediasec\r\n
Contact: <sip:+4953316***9001@212.110.197.66:10466;transport=TLS>\r\n
P-Asserted-Identity: <sip:+4953316***9001@tel.t-online.de;user=phone>\r\n
Content-Type: application/sdp\r\n
Content-Length: 1014\r\n
\r\n
v=0\r\n
o=- 2193767683 2193767683 IN IP4 212.110.197.66\r\n
s=call\r\n
c=IN IP4 212.110.197.66\r\n
t=0 0\r\n
m=audio 13852 RTP/SAVP 98 97 8 0 3 101\r\n
a=rtpmap:98 speex/16000\r\n
a=rtpmap:97 speex/8000\r\n
a=rtpmap:8 PCMA/8000\r\n
a=rtpmap:0 PCMU/8000\r\n
a=rtpmap:3 GSM/8000\r\n
a=rtpmap:101 telephone-event/8000\r\n
a=fmtp:101 0-15\r\n
a=crypto:100 AES_256_CM_HMAC_SHA1_80 inline:ZAZosXeX/AhEIadZlN+bZ7l0/DS+i/4fPz0gRFs/LgDkDyg7yPCLboheBzX+WA==\r\n
a=crypto:101 AES_256_CM_HMAC_SHA1_32 inline:I55+04kBOU4F17hc3sLDNksippeO40n0MZzcLlI58q1BvbtSjvMGFXJgCyaDuQ==\r\n
a=crypto:102 AES_192_CM_HMAC_SHA1_80 inline:S0Y0v70v6uRJYcfEzeYM/VOuwINZLmKuakdkOYy+GxW+Hr7gLB4=\r\n
a=crypto:103 AES_192_CM_HMAC_SHA1_32 inline:uIFzidDCiCdub7iwV3fdrmAsUqpUmx+ctf1ynHObhGjZyn4PPGg=\r\n
a=crypto:104 AES_CM_128_HMAC_SHA1_80 inline:obZUFixZHar0d2OCpLQyaoJ04X+stIoXUji4hIoT\r\n
a=crypto:105 AES_CM_128_HMAC_SHA1_32 inline:95vAQmzHR3QTxqp3UFDNl0llG1wJ7aJZPr1TZZmM\r\n
a=crypto:106 F8_128_HMAC_SHA1_80 inline:ImeQJ3qP7QUpE/lx68lITpCu3X5PhXM6eKcTqphm\r\n
a=3ge2ae:requested\r\n
a=sendrecv\r\n
a=ptime:20\r\n

[SIP-Packet] 2020/09/17 23:57:03,914  Devicetime: 2020/09/17 23:57:06,252 [Packet]: 
Receiving datagram (326 Bytes) at 212.110.197.66:10466 from 217.0.21.68:5061 using TLS (RtgTag 0):
SIP/2.0 100 Trying\r\n
Via: SIP/2.0/TLS 212.110.197.66:10466;received=212.110.197.66;rport=10466;branch=z9hG4bK-f36961de-62314e2a\r\n
To: <sip:+4953319****5@tel.t-online.de>\r\n
From: <sip:+4953316***9001@tel.t-online.de;user=phone>;tag=-1947401466--1606031634\r\n
Call-ID: 3740630087@00a0572bb1da\r\n
CSeq: 101 INVITE\r\n
Content-Length: 0\r\n
\r\n

Schöne Grüße

Maik Weidemann