[NNagain] Flash priority

[rjmcmahon]

> [JL] Quite true: each network tends to use DSCP marks on a
> private/internal basis and so will bleach the DSCP marks on ingress
> from peers. This will, however, change with the upcoming IETF RFC on
> Non-Queue-Building (NQB) Per Hop Behavior -
> https://datatracker.ietf.org/doc/html/draft-ietf-tsvwg-nqb. And I can
> report that we at Comcast now permit DSCP-45 inbound for NQB packets,
> in case developers would like to experiment with this (we just
> finished updating router configs last week for residential users on
> DOCSIS; FTTP and commercial are still in process).

iperf 2 now supports a --dscp option as a convenience (vs setting the 
--tos byte.) I can confirm --dscp 45 is being passed over my xfinity hop 
to my linodes (now Akamai) servers in both directions at multiple colo 
locations.

The --dscp is in the master branch. 
https://sourceforge.net/p/iperf2/code/ci/master/tree/  Older versions 
require --tos and setting the byte, e.g. 180

Bob