[AG-TECH] Combining 2.4 and 3.0 venue servers

[Andrew A Rowley]

Hi,

With the multicast loopback disabled in the quickbridge code, I think that this would work fine, but you would need to do this in both the 2.4 and 3.0.2 quickbridge installations.  This would mean that traffic sent from say the 2.4 bridge would go into multicast, and be looped back to the machine again, so both the 2.4 and 3.0.2 bridges would receive the packet and forward it back to the unicast clients.  Provided the unicast clients don't then forward it back to the bridge, there should be no looping.

Note that this requires both servers to be set up with statically assigned multicast addresses, with the same address used for the same venue on both servers.  This will not work otherwise.

Andrew :)

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> -----Original Message-----
> From: Jeremy Mann [mailto:jeremymann at gmail.com]
> Sent: 06 February 2007 15:43
> To: Andrew.Rowley at manchester.ac.uk
> Cc: ag-tech
> Subject: Re: [AG-TECH] Combining 2.4 and 3.0 venue servers
> 
> On 2/6/07, Andrew A Rowley <Andrew.Rowley at manchester.ac.uk> wrote:
> > Hi,
> >
> > The reason that you cannot have two bridge servers on the same machine
> is that QuickBridge disables the return of multicast packets to the
> sending machine (known as multicast loopback), so packets sent by one
> bridge cannot be received by the other.  If you need to do this, you would
> need to modify quickbridge.  This could cause a looping of packets (it
> shouldn't do, but I could not have thought of something).
> 
> Andrew, how would the unicast bridge be affected by this when bridging
> a 3.x client with a 2.4 server? Say we have 2 Ag servers, 1 2.4 the
> other 3.0.2 broadcasting to the same multicast addresses, but they
> each run their own unicast bridge server. Now if  3.x client connects
> to one of the "shared" venues, how would the bridge function and place
> them in the correct space so everybody else in the room will see them?
> 
> --
> Jeremy Mann
> jeremy at biochem.uthscsa.edu
> 
> University of Texas Health Science Center
> Bioinformatics Core Facility
> http://www.bioinformatics.uthscsa.edu
> Phone: (210) 567-2672