[AG-TECH] VPCscreen TTL (patch for VPMedia)

Christoph Willing c.willing at uq.edu.au
Fri Apr 2 09:30:25 CDT 2010

On 02/04/2010, at 10:39 PM, Philippe d'Anfray wrote:

> Bonjour
> Great !!  with this test version of VPCScreen, the multicast packets  
> are
> given a TTL of 127 and can be received normally at other multicast
> locations (at least in France....) (and also through bridges).

OK, thanks for raising the problem and doing the test Philippe.

And also thanks to Andrew Rowley for suggesting a ttl issue as the  
cause of the problem!

This change should be applied to all the various release packages.  
Attached below is the patch I've used - it just sets a default ttl of  
127. A better fix would be to use whatever the user asks for, so if  
anyone has time ....


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> Christoph Willing a ?crit :
>> Philippe,
>> Could you try some tests with:
>>    http://www.vislab.uq.edu.au/debuntu/tests/ 
>> vpcscreen_0.2-4_amd64.deb
>> You'll have to download manually and use dpkg to install (rather than
>> apt-get etc.):
>>    sudo dpkg -i vpcscreen_0.2-4_amd64.deb
>>>> Anyway, I think I've found the cause in the vpcscreen code and will
>>>> apply a simple minded fix for testing. Would you be able to test  
>>>> it? I
>>>> can't easily replicate your problem here to confirm that the fix
>>>> works. If you are able to help with the testing, could you confirm
>>>> that you're using Ubuntu 9.10 and whether you're using 32 or 64bit
>>>> version please, so that I can build the appropriate version for  
>>>> you?
> <Philippe_d-Anfray.vcf>

Christoph Willing                       +61 7 3365 8316
QCIF Access Grid Manager
University of Queensland

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