[Serusers] RTP being sent to wrong port

Andrey Kuprianov andrey.kouprianov at gmail.com
Fri Sep 22 08:31:39 CEST 2006


Hi,

Well, that makes my client one of those in your list then. ;-) Anyway,
Im still having problem. This code from the old SIP Comm project that
Im using, is a complete mess! Tried to assign same ports for receiver
and transmitter, but nothing happened. Now the transmitter's not
working, so I end up with no audio at all, when my friend is behind
NAT. Hehehe :) Gotta try out Java forum, maybe they can suggest
something.

Btw, if anyone is interested in old SIP Comm. bugs, the class that
handles media (i think it was called MediaManager or smth.. look
inside openMediaStreams() function), it's been assigning remote port
from remote SDP as its local port, therefore, completely disregarding
local SDP that it used to send in INVITE. I've changed it to use local
SDP and ended up with an assymetric client. :) So, now I need to
somehow change it back to a symmetric one.

  Andrey.


On 9/22/06, Jiri Kuthan <jiri at iptel.org> wrote:
> The client should be then fixed or exchanged. It is not yet a BCP RFC or so,
> but it should be soon. In the meantime it is just an informal but important
> practice to build clients in a symmetric way. I'm actually aware of few
> that are not build this way.
>
> -jiri
>
> At 18:12 20/09/2006, Andrey Kuprianov wrote:
> >Just looked up the code to make sure... :) It's definitely assymetric!
> >Thanks Vamsi!!!
> >
> >On 9/20/06, Vamsi Pottangi <vamsipottangi at gmail.com> wrote:
> >>
> >>Symmetric client uses the same port to send and receive messages.
> >>
> >>
> >>On 9/20/06, Andrey Kuprianov <andrey.kouprianov at gmail.com > wrote:
> >>> Forgive my ignorance. I know the term "symmetric client", but i dont
> >>> really know what that means. Can u please explain or just give me some
> >>> doc/rfc to read? :)
> >>>
> >>>    Andrey.
> >>>
> >>> On 9/20/06, Vamsi Pottangi < vamsipottangi at gmail.com> wrote:
> >>> >
> >>> > Is your application symmetric?
> >>> >
> >>> >
> >>> > On 9/20/06, Andrey Kuprianov < andrey.kouprianov at gmail.com> wrote:
> >>> > >
> >>> >    Hi,
> >>> >
> >>> > Im facing this problem for a few days already. Hope someone might have
> >>> > an idea or two. It's a long email too, btw.
> >>> >
> >>> > Im testing my app behind NAT's with SER-0.9.6 + mediaproxy + Asterisk
> >>> > (conf server). While X-Lite works *fine* and I get 2 way audio always,
> >>> > my app seems to have some kind of weird bug and I end up with 1 way
> >>> > audio stream.
> >>> >
> >>> > Here's the thing. Application starts receiver and transmitter on
> >>> > completely different ports. Here's SDP for remote and local machines
> >>> > (public IP's been x'ed by myself, of course):
> >>> >
> >>> > This one's sent in INVITE message to SER ==>
> >>> > 69563 DEBUG media.MediaManager - Local SDP: (this one's from local
> >>machine)
> >>> > v=0
> >>> > o=xps 1158739216750 1158739216757 IN IP4 192.168.1.3
> >>> > s=MC
> >>> > c=IN IP4 192.168.1.3
> >>> > t=0 0
> >>> > m=audio 25000 RTP/AVP 0 8
> >>> > a=rtpmap:0 PCMU/8000
> >>> > a=rtpmap:8 PCMA/8000
> >>> > a=sendrecv
> >>> >
> >>> > This one's sent with 200 OK from SER ==>
> >>> > 69563 DEBUG media.MediaManager - Remote SDP:
> >>> > v=0
> >>> > o=root 2500 2500 IN IP4 203.159.x.x
> >>> > s=session
> >>> > c=IN IP4 203.159.x.x
> >>> > t=0 0
> >>> > m=audio 30004 RTP/AVP 0 8
> >>> > a=rtpmap:0 PCMU/8000
> >>> > a=rtpmap:8 PCMA/8000
> >>> > a=silenceSupp:off - - - -
> >>> >
> >>> > The further log shows that transmitters and receivers have started on
> >>> > the proper IP/port ==>
> >>> >
> >>> > 69594 DEBUG media.AVReceiver -  Start listening for RTP @ addr:
> >>> > 192.168.1.3 port: 25000 ttl: 1
> >>> > 69657 DEBUG media.AVTransmitter - Created transmitter for:
> >>> > [203.159.x.x] at ports: [30004] encoded as: [[ULAW/rtp, alaw]]
> >>> > 69657 DEBUG media.MediaManager - Starting transmission
> >>> > 69672 DEBUG media.AVTransmitter - Track 0 is set to transmit as:
> >>> > ULAW/rtp, 8000.0 Hz, 8-bit, Mono, FrameSize=8 bits
> >>> > 69860 INFO media.AVTransmitter - Binded to port 30004
> >>> > 69875 DEBUG media.AVTransmitter - Started transmitting track 0 encoded
> >>> > as ULAW/rtp @ [203.159.x.x]:30004
> >>> >
> >>> > Nevertheless, the Ethereal capture shows that mediaproxy sends the
> >>> > stream NOT to port 25000 (local port), but to port 30004 (remote
> >>> > port)!! Why? This is not the case with X-Lite, however. Xlite captures
> >>> > show that streams are sent to proper ports always. Btw, Im attaching
> >>> > SIP+RTP Ethereal captures with this mail. Please, take a look.
> >>> >
> >>> > I also want to mention, that this doesnt happen with my app. for all
> >>> > the NATed nets. In some nets it works fine, but not in this one. Just
> >>> > weird.
> >>> >
> >>> > Please, let me know if anyone has ideas or hints regarding this nonsence
> >>:)
> >>> >
> >>> >    Bests,
> >>> >
> >>> >     Andrey.
> >>> >
> >>> >
> >>> > _______________________________________________
> >>> > Serusers mailing list
> >>> > Serusers at lists.iptel.org
> >>> > http://lists.iptel.org/mailman/listinfo/serusers
> >>> >
> >>> >
> >>> >
> >>> >
> >>> >
> >>> _______________________________________________
> >>> Serusers mailing list
> >>> Serusers at lists.iptel.org
> >>> http://lists.iptel.org/mailman/listinfo/serusers
> >>>
> >>
> >_______________________________________________
> >Serusers mailing list
> >Serusers at lists.iptel.org
> >http://lists.iptel.org/mailman/listinfo/serusers
>
> --
> Jiri Kuthan            http://iptel.org/~jiri/
>
>



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