Re: reserved flags and extensions

On 14 July 2014 06:36, Poul-Henning Kamp <phk@phk.freebsd.dk> wrote:

>
> The problem with low-fidelity implementations is that they, as the
> name says, are not going to pay a lot of attention to what we write
> they should do.
>
> We sort of have an unstated (should we?) principle so far of "I
> allow but You choose" attitude to variance from the base protocol,
> if we stick to that, all extensions/variances MUST be announced
> in SETTINGS, but the other end is not obligated to actually use them.
>
> Given that, low-fidelity proxies can simply strip anything from
> SETTINGS they don't understand.
>
>
This issue of announcing extensions in settings, and the chance for lo-fi
implementations to mangle things (e.g. forward settings but drop frames)
was the main reason I decided to alter my encoded-data extension draft [1]
to use a custom frame type to announce support for encodings, rather than a
setting. It has other benefits, but that was the main driver. I begin to
suspect that it will be nigh impossible to build an extension that modifies
existing frames or framing and works on the open internet, for this exact
reason. Thus all extensions under the banner of "h2" will have to be new
things (new settings, or new frame types).

[1] http://phluid61.github.io/internet-drafts/http2-encoded-data/


-- 
  Matthew Kerwin
  http://matthew.kerwin.net.au/

Received on Monday, 14 July 2014 00:25:05 UTC