SETTINGS_PRIORITY_SCHEME | Re: Setting to disable HTTP/2 Priorities

[Kari Hurtta <[e-mail]>]

> From the draft:
> 
> " 3.  The SETTINGS_ENABLE_HTTP2_PRIORITIES SETTINGS Parameter
> " 
> "    This document adds a new SETTINGS parameter to those defined by
> "    [RFC7540], Section 6.5.2.
> " 
> "    The new parameter name is SETTINGS_ENABLE_HTTP2_PRIORITIES.
> 
> Including "HTTP2" in the name is superfluous:  Since this is an
> HTTP/2 setting, it deals with HTTP/2 priorities.
> 
> Or was "HTTP2" added to the name to differentiate it from possible
> future priority mechanisms?  In that case, I suggest s/HTTP2/RFC7540/
>
>  - Dmitri.

Why boolean ("ENABLE") ?

I suggests SETTINGS Parameter

SETTINGS_PRIORITY_SCHEME

with values

 • 0             Sender of SETTINGS frame indicates that
                 it does not process or send priority 
                 values

 • 1             Sender of SETTINGS frame indicates that
                 it process or send RFC7540 priorities

 • unknown value (for recipient of SETTINGS frame)

                 Sender of SETTINGS frame indicates that
                 it is willing process some priority information  
                 or that it sends some priority information
                 (but recipient of SETTINGS frame does
                  not recognize these priorities)


Default value for SETTINGS_PRIORITY_SCHEME is 1
( RFC7540 priorities aka current HTTP/2 tree priorities).

Peer of HTTP/2 connection should send SETTINGS frame
with SETTINGS_PRIORITY_SCHEME once

Peer of HTTP/2 connection may send second SETTINGS frame
with SETTINGS_PRIORITY_SCHEME if it's value is same
than which it is received for peer on SETTINGS frame.


That is:
    Suggest SETTINGS_PRIORITY_SCHEME once
    and send SETTINGS_PRIORITY_SCHEME second time
    after that when you agreed with peer.


That makes SETTINGS_PRIORITY_SCHEME switch to
new priority scheme (when that is defined).

/ Kari Hurtta