Re: [tsvwg] updated version of QCI to Diffserv draft

[Subir Das <[e-mail]>]

Hello Jerome,

 I read your ver-01 draft and have the following questions and comments.

- What is the motivation of this draft in IETF when 3GPP is the responsible
organization to create such a mapping document?

- Who will be using these recommendations if such a document exists in IETF?

- What is the intent of this document: Informational or Experimental or
Standards Track?


You cited 3GPP TS 23.203 QCIs mapping table as defined in TS 23.303, but I
assume you understand that these QCIs to services mappings are examples
only (as clearly mentioned in the service column). The correct mapping is
done by the network operators based on their use cases / services and it
does follow the IETF guidance on QoS treatment.  In some use cases, these
mappings are not implemented simply based on QCIs, it uses other parameters
such as ARP (Allocation and Retention Priority).  Therefore, it makes sense
to keep them as examples as 3GPP specifies in their document since these
mappings are done based on operator’s policy and should not be a
recommendation.



Moreover, the draft has several issues. For example, it  proposes to put
all dialer/conversational voice in a single category with DSCP value 44
(101100)/Voice Admit without differentiating the normal voice signaling and
media with ETS (Emergency Telecommunication Service) voice signaling and
media.  This conflicts with ATIS-1000063 that specifies DSCP 46 (101110)/EF
for normal voice signaling and media and DSCP 44 (101100)/Voice Admit for
ETS signaling and media. It also conflicts with RFC 5865, which requires
differentiation between traffic associated with capacity admitted vs.
non-capacity admitted IP telephony sessions.


IMO, IETF community SHOULD NOT  create a document that recommends the
QCI-to-DSCP mappings unless 3GPP asks for it via a liaison.



Thanks,

-Subir


Re: [tsvwg] updated version of QCI to Diffserv draft

"Jerome Henry (jerhenry)" <[e-mail]> Mon, 15 April 2019 17:07 UTCShow
header <https://mailarchive.ietf.org/arch/browse/tsvwg/?q=Jerome#>

Dear all,

We submitted an update to the Diffserv to QCI mapping document. As
part of the 5G finalization, then 3GPP added a few  QCIs, and we
updated the draft accordingly.

We are looking forward to input and feedback, through the mailer and
in Montreal. Our ambition is to (eventually) get this draft to a
consensus state where we can share it with GSMA, who documents how QCI
markings can be translated to other values when exchanged through
other domains (e.g. Diffserv) between carriers.

Thanks!

Jerome

https://datatracker.ietf.org/doc/draft-henry-tsvwg-diffserv-to-qci/