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UDP merging vs VoIP

Posted Nov 1, 2009 11:00 UTC (Sun) by NAR (subscriber, #1313)
In reply to: UDP merging vs VoIP by intgr
Parent article: JLS2009: Generic receive offload

I think VoIP doesn't mind if a couple of packets is lost (that's why it uses UDP in the first place), the jitter is more problematic. Buffering doesn't really help, because in a phone conversation one might want to interrupt what the other says and seconds of buffering kind of breaks this.

I'm not quite sure where this merging could be done. Only at the endpoints or in routers between?

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UDP merging vs VoIP

Posted Nov 1, 2009 16:58 UTC (Sun) by intgr (subscriber, #39733) [Link]

From the article:
> If a system is serving as a router, it really should not be changing the
> headers on packets as they pass through.

Also, VOIP uses UDP simply because TCP would add additional delay when it attempts to retransmit packets that already missed their deadline.

But VOIP is still affected by packet loss. A UDP packet that missed its deadline is never way any worse than a UDP packet that got dropped.