[rtcweb] Ben Campbell's Yes on draft-ietf-rtcweb-fec-08: (with COMMENT)

[Ben Campbell <[e-mail]>]

Ben Campbell has entered the following ballot position for
draft-ietf-rtcweb-fec-08: Yes

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COMMENT:
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Thanks for this effort. I am balloting "yes", but have some minor comments:

§8:
- "Given this, WebRTC implementations SHOULD consider using RTX or
flexfec retransmissions instead of FEC when RTT is low,"

"consider" seems vague for a normative requirement. Can you describe concrete
requirements? Otherwise I suggest descriptive language.

Can you give guidance on what RTT would be reasonable to consider as "low"?

- "Note that when probing bandwidth, i.e., speculatively sending extra
data to determine if additional link capacity exists, FEC SHOULD be
used in all cases."

I assume the point of this is the redundant FEC data should _be_ that extra
data. But one could read this to mean that, if you are already sending extra
data, you should also use FEC.

§9, 2nd paragraph:

I'm by no means an expert in this, and leave it to the crypto experts to know
if this matters, but does the additional redundancy of FEC have any impact on
SRTP encryption?