Hi All.<br>
<br>
Below is a snippet of an INVITE and you can see the usual "trying -
your call is important to us" in the dialog. Anyhow, for some reason
SER occasionally attempts to sent the ACK to itself, which causes a
looping condition. The last ACK shown is the start of the looping
condition.<br>
<br>
It only happens on occasion. SER should have consumed the ACK rather than attempted to forward it.<br>
<br>
Can anyone explain this?<br>
<br>
Regards,<br>
Paul<br>
<br>
IP Legend<br>
-------------------<br>
<a href="http://10.3.0.221">10.3.0.221</a> - SER (behind a Cisco 3600 so ALG rewrote the IPs)<br>
<a href="http://69.36.46.178">69.36.46.178</a> - NATed SIP UA<br>
<br>
U 2005/04/15 02:19:16.252614 <a href="http://69.35.46.178:5060">69.35.46.178:5060</a> -> <a href="http://10.3.0.221:5060">10.3.0.221:5060</a><br>
INVITE <a href="mailto:sip:8187768080@sipdev.mycompany.net">sip:8187768080@sipdev.mycompany.net</a> SIP/2.0.<br>
Via: SIP/2.0/UDP <a href="http://192.168.1.102:5060">192.168.1.102:5060</a>;branch=z9hG4bK3915905414.<br>
From: Test User <<a href="mailto:sip:3215591439@sipdev.mycompany.net">sip:3215591439@sipdev.mycompany.net</a>>;tag=1465261089.<br>
To: <<a href="mailto:sip:8187768080@sipdev.mycompany.net">sip:8187768080@sipdev.mycompany.net</a>>.<br>
Call-ID: <a href="mailto:2671219156@192.168.1.102">2671219156@192.168.1.102</a>.<br>
CSeq: 101 INVITE.<br>
Contact: <sip:3215591439@192.168.1.102:5060>.<br>
Proxy-Authorization: Digest username="3215591439",
realm="<a href="http://sipdev.mycompany.net">sipdev.mycompany.net</a>",
nonce="425f5e0de25efdb3f5a6125dcf2147bf30fe9177",
uri="<a href="mailto:sip:8187768080@sipdev.mycompany.net">sip:8187768080@sipdev.mycompany.net</a>",
response="61996c3bdc10990fec7e245751777516", algorithm=MD5,
cnonce="ae02e47a3355bada49ce344c92f48587", qop=auth, nc=00000002.
max-forwards: 70.<br>
Allow: INVITE, ACK, CANCEL, BYE, REFER, NOTIFY.<br>
Content-Type: application/sdp.<br>
Content-Length: 180.<br>
.<br>
v=0.<br>
o=- 32014 3005 IN IP4 <a href="http://192.168.1.102">192.168.1.102</a>.<br>
s=-.<br>
c=IN IP4 <a href="http://192.168.1.102">192.168.1.102</a>.<br>
t=0 0.<br>
m=audio 13456 RTP/AVP 18 0 8 2 4 101.<br>
a=rtpmap:101 telephone-event/8000.<br>
a=fmtp:101 0-15.<br>
a=ptime:20.<br>
.<br>
<br>
#<br>
U 2005/04/15 02:19:16.276216 <a href="http://10.3.0.221:5060">10.3.0.221:5060</a> -> <a href="http://69.35.46.178:5060">69.35.46.178:5060</a><br>
SIP/2.0 100 trying -- your call is important to us.<br>
Via: SIP/2.0/UDP <a href="http://192.168.1.102:5060">192.168.1.102:5060</a>;branch=z9hG4bK3915905414;rport=5060;received=<a href="http://69.35.46.178">69.35.46.178</a>.<br>
From: Test User <<a href="mailto:sip:3215591439@sipdev.mycompany.net">sip:3215591439@sipdev.mycompany.net</a>>;tag=1465261089.<br>
To: <<a href="mailto:sip:8187768080@sipdev.mycompany.net">sip:8187768080@sipdev.mycompany.net</a>>.<br>
Call-ID: <a href="mailto:2671219156@192.168.1.102">2671219156@192.168.1.102</a>.<br>
CSeq: 101 INVITE.<br>
Content-Length: 0.<br>
.<br>
<br>
#<br>
U 2005/04/15 02:19:16.792795 <a href="http://69.35.46.178:5060">69.35.46.178:5060</a> -> <a href="http://10.3.0.221:5060">10.3.0.221:5060</a><br>
ACK <a href="mailto:sip:8187768080@sipdev.mycompany.net">sip:8187768080@sipdev.mycompany.net</a> SIP/2.0.<br>
Via: SIP/2.0/UDP <a href="http://192.168.1.102:5060">192.168.1.102:5060</a>;branch=z9hG4bK3499714875.<br>
From: Test User <<a href="mailto:sip:3215591439@sipdev.mycompany.net">sip:3215591439@sipdev.mycompany.net</a>>;tag=1465261089.<br>
To: <<a href="mailto:sip:8187768080@sipdev.mycompany.net">sip:8187768080@sipdev.mycompany.net</a>>;tag=cdbfe46960d7566fcbe09f199f2b328d.c2bb.<br>
Call-ID: <a href="mailto:2671219156@192.168.1.102">2671219156@192.168.1.102</a>.<br>
CSeq: 100 ACK.<br>
Content-Length: 0.<br>
.<br>
<br>
#<br>
U 2005/04/15 02:19:16.912146 <a href="http://10.3.0.221:5060">10.3.0.221:5060</a> -> <a href="http://10.3.0.221:5060">10.3.0.221:5060</a><br>
ACK <a href="mailto:sip:8187768080@sipdev.mycompany.net">sip:8187768080@sipdev.mycompany.net</a> SIP/2.0.<br>
Max-Forwards: 10.<br>
Record-Route: <sip:<a href="http://10.3.0.221">10.3.0.221</a>;ftag=1465261089;lr>.<br>
Via: SIP/2.0/UDP <a href="http://10.3.0.221">10.3.0.221</a>;branch=0.<br>
Via: SIP/2.0/UDP <a href="http://192.168.1.102:5060">192.168.1.102:5060</a>;received=<a href="http://69.35.46.178">69.35.46.178</a>;branch=z9hG4bK3499714875.<br>
From: Test User <<a href="mailto:sip:3215591439@sipdev.mycompany.net">sip:3215591439@sipdev.mycompany.net</a>>;tag=1465261089.<br>
To: <<a href="mailto:sip:8187768080@sipdev.mycompany.net">sip:8187768080@sipdev.mycompany.net</a>>;tag=cdbfe46960d7566fcbe09f199f2b328d.c2bb.<br>
Call-ID: <a href="mailto:2671219156@192.168.1.102">2671219156@192.168.1.102</a>.<br>
CSeq: 100 ACK.<br>
Content-Length: 0.<br>
P-hint: Local Destination.<br>
<br>