Subject: Re: [rmcat] New Version Notification for draft-singh-rmcat-adaptive-fec-01.txt

From: Randell Jesup <[email-masked]>
Date: Sun, 09 Nov 2014 14:34:24 -0500

On 10/24/2014 12:00 PM, Varun Singh wrote:
> Name: draft-singh-rmcat-adaptive-fec

Following up on comments in the interim:

1) Adaptive FEC helps you (compared to just increasing encoder rate) in 
two cases:
    a) very short queue or some form of AQM, where going over the 
available bandwidth rapidly results in loss instead of queuing delay
    b) Very delayed encoder rate changes, or (maybe) very low frame rate 
combined with a close-to-rate pacing buffer.  These would make it hard 
to probe without problems backing off fast enough.

   It does not help you in the "normal" case.

2) This implies you should use it opportunistically when the current 
conditions imply the cases in #1 are true (when you see that increase in 
sending rate results in loss and not delay, inferring this is AQM or 
very short queuing (or an already-full-queue).  You should also verify 
and leave this mode if the prerequisites change, since the actual 
bottleneck could move from one link to another during a call

-- 
Randell Jesup -- rjesup a t mozilla d o t com