Re: [Bloat] [Cerowrt-devel] FQ_Codel lwn draft article review

[Oliver Hohlfeld <oliver@net.t-labs.tu-berlin.de>]

On 11/28/2012 08:45 PM, Simon Barber wrote:
> Not sure why you would use mean latency - for VoIP the thing that
> matters is maximum latency -

Latency matters, but only when assessing conversational quality, i.e., 
involving two parties and their turn taking behavior. Latency does not 
affect the quality of an unidirectional audio stream. The latter is only 
affected by packet loss. Note that jitter translates into packet loss at 
application layer by the de-jitter buffer (audio frame discards), when 
the packets arrive after their scheduled playout time. If they arrive 
before, they don't affect the call quality.

> if some packets are late, then you don't hear them.

To my understanding, this is generally referred to as jitter.

> More precisely a small packet loss rate is OK

How small is small?

What is tolerable depends on other parameters such as the used code, 
whether packet loss concealment is turned on etc.

--Oliver