Re: [tsvwg] Considerations for assigning new DSCPs

Martin Duke <> Fri, 26 February 2021 23:42 UTC

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From: Martin Duke <>
Date: Fri, 26 Feb 2021 15:42:11 -0800
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To: Ana Custura <>
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Subject: Re: [tsvwg] Considerations for assigning new DSCPs
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Hi Ana,

Thanks very much for this work! This is an intenseful useful and concise
document, which is the best kind. I hope this rapidly gets in shape where
it can be adopted.

One nit in Section 4:

Reset-some-low:  sets the last three bits on all traffic to 0b000,
      unless the first two bits (the former precedence bits) are 0b11;

It might help to clarify that you mean the first two bits of the entire
DSCP field, not the fourth and fifth bits of that field (i.e. the first two
of the last three).

On Sun, Feb 21, 2021 at 10:01 AM Ana Custura <> wrote:

> Hi,
> Gorry and I put together a draft, we think this could provide useful input
> to new DSCP definitions.
> We aim to update this over the following months as we start a new set of
> DSCP transparency measurements across edge networks.
> Abstract:
>    This document discusses the considerations for assigning new DiffServ
>    Code Points (DCSPs).  It considers the common remarking behaviours
>    that the Diffserv field might be subjected to along an Internet path.
>    It also notes some implications of using a specific DSCP.
> The document can be found at
> We’d love any feedback and contributions on this.
> Ana, Gorry  & Raffaello