Hello Andrew,
It seems im also being troubled by the problem you have perfectly put
into words unlike the one in my email. ^_^
I just want to ask though, because when i use UDP as the protocol in
my rtc profile, this problem does not occur and communication flow
between user A and B goes smoothly.
Do you think there is an explanation behind that? Why would SER/RTCDLL
combination work when it's under UDP and not when using TCP?
I really have no idea, just observations.
Any comments and/or ideas regarding this issue would greatly help.
Thanks alot in advance.
- Jonathan -
On Wed, 18 Aug 2004 09:46:05 +1000, Andrew Mee
<andrew(a)healthshare.net.au> wrote:
After much more discovery we have figured out what the
issue is with the
MS RTC 1.2 and SER.
This isn't so much as a bug with SER but with MS RTC 1.2, it is caused
by MS RTC sending incorrect Request-URI in the headers. This only occurs
in request routed mode from the callee end.
Take the example:
RTC Client A SIP Server RTC Client B
-----INVITE-------------->
<----100 Trying-----------
-----INVITE---------------->
<----100 Trying-------------
<----180 Ringing---------- <----180 Ringing------------
<----200 OK w/ INVITE----- <----200 OK w/ INVITE-------
-----ACK-----------------> -----ACK------------------->
All is fine at this point, however now lets send a message from A to B:
RTC Client A SIP Server RTC Client B
----MESSAGE b@server----> ----MESSAGE b@server---->
<----200 OK ------------- <----200 OK --------------
All is still fine, However if we send a message back from B to A:
RTC Client A SIP Server RTC Client B
<----MESSAGE b@server----
-----MESSAGE b@server---->
<----481 Call Leg/T DNE---
This is obvious because the SER server sees this message as needing to
go back to B when it should be forwarded to A as per "8.1.1.1
Request-URI" of the rfc (as far as my understanding on this). This issue
occurs with BYE commands and possibly other types of commands.
I might add the To: and From: header fields are correct.
Solution to this problem could (or is there an existing way) a
module/control could be created that checks if the To: field doesn't
equal the request-uri that the request-uri be changed to the information
in the To: field?
Yes I agree that while this is a MS RTC problem, I figure this is going
to be a better/quicker short term solution. I have not tested if this
problem exists with other SIP servers.
I can send some ngrep logs if anyone likes?
--
Andrew Mee
_______________________________________________
Serusers mailing list
serusers(a)lists.iptel.org
http://lists.iptel.org/mailman/listinfo/serusers