Re: [Cerowrt-devel] [Make-wifi-fast] [tsvwg] Comments on draft-szigeti-tsvwg-ieee-802-11e

[David Lang <david@lang.hm>]

On Fri, 14 Aug 2015, Jonathan Morton wrote:

> The only mandatory form of aggregation in 'n' is of the one-checksum type,
> even though other types are permitted.  The overhead at the data layer is
> slightly less, and checksum failure handling on receive is simpler (just
> throw the whole thing out and nak it), as is handling the nak at the
> transmitter (just retransmit the whole aggregate at the next opportunity).
> Most 'n' hardware thus caters only to this lowest common denominator.
>
> I'm not sure whether soft-MAC type hardware (like ath9k) can also support
> the more flexible type via driver support - I would hope so - but hard-MAC
> hardware almost certainly can't be retrofitted in this way.

if the ath9k driver could support this, would this cause a problem on stock 
clients?

> However, since 'ac' hardware is required to support individual-checksum
> aggregation, a dual-band 'ac' card running on 2.4 GHz will effectively be
> an 'n' card with such support, even if it's a hard-MAC.

right, I'm looking at what I can do to improve things even on non-ac stuff.

David Lang