Re: Réf. : RE: Question on Continuity Counter field

[alain.ritoux@6wind.com]

Tarif.Zein-Alabedeen@space.alcatel.fr wrote:
> Thank you Art and william for your answers...
>
> William says that consider or mask CC check for a given PID is 
> implementation dependent.. is someone aware of the general rule for 
> current IP/MPE/MPEG implementations?
>
> Considering our ULE encapsulation, I think it would be wise to 
> provision an option allowing to disactivate CC check for specified 
> PIDs in the receiver.
I'm not that sure, because the countinuity counter shows some TS cells loss, which can be meesy wrt ULE re-assembly, so ignoring it may lead to strange packets (unless detetected by sizes issues). Of course such packets have very little chance to pass the CRC32 test, but an earlier drop prevents CPU usage for nothing.


> This may be helpful if, at some point in the future, we need ULE/MPEG 
> to operate correctly in a mesh or multi star scenarios (PID shared 
> among several transmiters).
The way ULE is designed doesn't seem to work with several independant transmitters, because reassembly of ULE SNDU is led only by PID, and if 2 SNDU ares sent by 2 transmitters, each splitting over many TS cells, the reciever, won't be able to tell whose fragment belongs to who, and hence won't be able to reconstruct any of the SNDUs.

my 2 cents.

Cheers.
Alain
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Alain RITOUX
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