Hi,
We have been
performing testing using the sipXphone and our line of scalable SIP
proxy
and RTP media server products for voice and video. LanScape voice and
video SIP server
products can be
reviewed at the following URLs:
Scalable Sip
Centrex Proxy server:
High performance
RTP Media proxy:
Some customers want to use the SipXphone so we perform
upfront interop testing to make sure
basic functionality works.
We wanted to
make a recomendation to you
regarding how your Contact headers are
being formatted.
We tested using SipXphone versioin 2.6.0.27
We noticed that your code
creates Contact headers something like:
Contact:
sip:10.0.0.2
instead
of:
sip:username (at) 10.0.0.2:port
What we would like
to see is that you always make sure the username is part of a contact
header.
The port value is
not so critical but the user name is really important to help reduce extra
proxy
procesing.
For example:
Here is a "200 Ok" response from the SipXphone after it decides it want to
accept
an
INVITE:
SIP/2.0 200 OK
From: 222
<sip:222 (at) lanscapecorp.dnsalias.com:7000>;tag=c923c43;x-UaId=xxxxx-yyyy-zzzzzz;x-PsId=4D724D22-A5AF-4C50-A01A-76B162933D64
To:
<sip:111 (at) lanscapecorp.dnsalias.com:7000>;tag=25882
Call-Id:
b217ba35-f6bb-4bb5-ba89-39b226fcbab3-000013b4 (at) 192.168.1.2Cseq:
210904266 INVITE
Content-Type: application/sdp
Content-Length:
163
Via: SIP/2.0/UDP
192.168.1.2:7000;branch=z9hG4bKf968a2ddba0e290a869b664c5acf6a178.0;received=70.92.187.124
Via:
SIP/2.0/UDP 192.168.1.2:10000;received=192.168.1.2:10000
Record-Route:
<sip:70.92.187.124:7000;lr>
Date: Mon, 30 Jan 2006 22:58:03
GMT
Contact: sip:10.0.0.2
Allow: INVITE, ACK, CANCEL, BYE, REFER,
OPTIONS, NOTIFY, REGISTER, SUBSCRIBE
User-Agent: sipX/2.5.2
(WinNT)
Accept-Language: en
Supported: sip-cc, sip-cc-01, timer,
replaces
v=0
o=sipX 5 5
IN IP4 10.0.0.2
s=phone-call
c=IN IP4 10.0.0.2
t=0 0
m=audio 13002
RTP/AVP 0 101
a=rtpmap:0 pcmu/8000/1
a=rtpmap:101
telephone-event/8000/1
Our SIp server products perform complex SIP protocol
fixups when they detect that things are not
quite right with the received
SIP protocol data (the exact same way a dedicated session border
controller
operates). In this case, our server code fixed up things as expected but had
to perform
more processing than normal. Tha'ts what caught our
eye.
Anyway, please check the SIP RFC and try to format
your Contact headers using username (at) host:port syntax.
Thanks and happy VOIPing!
LanScape support