[AG-TECH] VenueServer Multicast/Unicast Question

Andrew A Rowley Andrew.Rowley at manchester.ac.uk
Thu Apr 6 02:51:18 CDT 2006


This could mean that your bridge server has bad multicast.  To explain in more detail:

1) When everyone uses multicast everything is good.  This means that the sites have good multicast connectivity between them.  Note that no multicast traffic is flowing to/from the bridge server in this situation.

2) If everyone uses unicast everything is good.  This means that all traffic is now flowing to and from the bridge server.  No traffic is flowing directly between sites.  Multicast is not used at all, as the bridge server is forwarding all traffic it receives directly to each of the clients.

3) If some use unicast and some use multicast, sometimes those using multicast loose the video stream but keep the audio stream.  Those using multicast get good connectivity as per situation 1.  The bridge server must also be sending out good multicast traffic, but is having problems receiving the traffic, as shown by the fact that the unicast clients sometimes loose video.  This could be due to any number of factors, e.g. the routers could be set up so that multicast traffic is a low priority, or multicast could just not be set up correctly on the routers.

Hope this helps you diagnose your problem,

Andrew :)

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Email: Andrew.Rowley at manchester.ac.uk
From: owner-ag-tech at mcs.anl.gov [mailto:owner-ag-tech at mcs.anl.gov] On Behalf Of west suhanic
Sent: 05 April 2006 23:52
To: ag-tech at mcs.anl.gov
Subject: [AG-TECH] VenueServer Multicast/Unicast Question

Hello All:

I run some venue servers and bridge servers on FreeBSD-(v5.4) and Fedora Core 4.
The problem I am having is the following:

1)If every one uses multicast into the venue server everything is good.
2)if every one uses unicast into the venue server everything is good.

3)If some use multicast and some use unicast then sometimes those
using unicast loose the video stream but keep the audio stream.

This problem exists under AGtkv2.4 and AGtk v2.3. 

Any help/suggestions would be appreciated.


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