I am an assigned INT directorate reviewer for <draft-ietf-tsvwg-nqb-24.txt>. These comments were written
primarily for the benefit of the Internet Area Directors. Document editors and shepherd(s) should treat these comments just like they would treat comments from any other IETF contributors and resolve them along with any other Last Call comments that have been received. For more details on the INT Directorate, see https://datatracker.ietf.org/group/intdir/about/ .

Based on my review, if I was on the IESG I would ballot this document as NO OBJECTION.

SUMMARY:
The draft introduces a differentiated services code point for traffic where latency is important. The primary focus is for applications such as IoT and video conferencing.  However, the threshold for low bit rate assumes network connectivity at least as good as provided by 5G mobile networks. Many places in the world still have 4G and even 3G networks.  Remote locations may only be served by satellite.  Many IoT applications are not latency sensitive, but are low bit rate - for example environment recording applications - but it is probably not good to differentiate these from latency sensitive low bit rate applications such as sending remote terminal input.  Many video conferencing applications (for example Meetecho) offer possibilities to turn of video feeds and just have audio and
screen sharing.  6G is also being developed and when deployed will likely take time to replace 4G and 5G, so some more thought on thresholds for NQB PHB is needed.

SPECIFIC COMMENTS:

In section 4.1 500Kb/s is quite high on 4G mobile networks, typically what is used for video conferencing and can saturate end point link bandwidth.  Would expect this to also be high for satellite links. For IoT applications and voice probably 50Kb/s is sufficient.

Informative reference [SA-5G] is an ETSI document that has several versions, possibly the latest version 18.5.0 is the one being referred to.

Should there be references for Cubic and BBR in the introduction, perhaps RFC8312 for Cubic and https://github.com/google/bbr for BBR,as the draft https://datatracker.ietf.org/doc/html/draft-cardwell-iccrg-bbr-congestion-control-02 has expired.