[Cats] Re: What's next for CATS? Vienna and beyond

Adrian Farrel <adrian@olddog.co.uk> Mon, 01 June 2026 10:20 UTC

Return-Path: <adrian@olddog.co.uk>
X-Original-To: cats@mail2.ietf.org
Delivered-To: cats@mail2.ietf.org
Received: from localhost (localhost [127.0.0.1]) by mail2.ietf.org (Postfix) with ESMTP id B46DFF89A932 for <cats@mail2.ietf.org>; Mon, 1 Jun 2026 03:20:56 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ietf.org; s=ietf1; t=1780309256; bh=ztRRRZXzhKShMXn8BAN/TbHrln/+bGOx9s3qmxCrs/c=; h=Reply-To:From:To:Cc:References:In-Reply-To:Subject:Date; b=lJSP0+RbFKJ6WTdBW5yZQa3jcu7jejm3rAoRhH9kdHMKPwZFSQdR6GpKbn1kDhzzj EyFt85vTb7lmVgb5KeYXfWS/hivG0FNReRIx8zEypsIz+ALvuYcJ2JtFjxzqOKTk8e 5SWR7XqCEBs3pGg7z5gl3XNZuLReakuNcx9mNsek=
X-Virus-Scanned: amavisd-new at ietf.org
X-Spam-Flag: NO
X-Spam-Score: -2.797
X-Spam-Level:
X-Spam-Status: No, score=-2.797 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: mail2.ietf.org (amavisd-new); dkim=pass (2048-bit key) header.d=olddog.co.uk
Received: from mail2.ietf.org ([166.84.6.31]) by localhost (mail2.ietf.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 4Z4KbRhDY1Fx for <cats@mail2.ietf.org>; Mon, 1 Jun 2026 03:20:55 -0700 (PDT)
Received: from mta5.iomartmail.com (mta5.iomartmail.com [62.128.193.155]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail2.ietf.org (Postfix) with ESMTPS id 72F5FF89A92A for <cats@ietf.org>; Mon, 1 Jun 2026 03:20:55 -0700 (PDT)
Received: from vs2.iomartmail.com (vs2.iomartmail.com [10.12.10.123]) by mta5.iomartmail.com (8.14.7/8.14.7) with ESMTP id 651AK8P2007138; Mon, 1 Jun 2026 11:20:08 +0100
Received: from vs2.iomartmail.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7B77246056; Mon, 1 Jun 2026 11:20:07 +0100 (BST)
Received: from vs2.iomartmail.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7933446052; Mon, 1 Jun 2026 11:20:07 +0100 (BST)
Received: from asmtp3.iomartmail.com (unknown [10.12.10.224]) by vs2.iomartmail.com (Postfix) with ESMTPS; Mon, 1 Jun 2026 11:20:07 +0100 (BST)
Received: from LAPTOPK7AS653V (82-69-109-75.dsl.in-addr.zen.co.uk [82.69.109.75]) (authenticated bits=0) by asmtp3.iomartmail.com (8.14.7/8.14.7) with ESMTP id 651AK6Nx006757 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 1 Jun 2026 11:20:06 +0100
From: Adrian Farrel <adrian@olddog.co.uk>
To: 'Jing Wang' <wangjingjc@chinamobile.com>
References: <048e01dcedc8$09061d30$1b125790$@olddog.co.uk> <2026060115294614969713@chinamobile.com>
In-Reply-To: <2026060115294614969713@chinamobile.com>
Date: Mon, 01 Jun 2026 11:20:05 +0100
Organization: Old Dog Consulting
Message-ID: <0a5201dcf1b0$37a8f4f0$a6faded0$@olddog.co.uk>
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="----=_NextPart_000_0A53_01DCF1B8.996DF930"
X-Mailer: Microsoft Outlook 16.0
Content-Language: en-gb
Thread-Index: AQKT3DB9trhrmhWwRnzyHSumQZF88AHqmF26tKxKRPA=
X-Originating-IP: 82.69.109.75
X-Thinkmail-Auth: adrian@olddog.co.uk
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; d=olddog.co.uk; h=reply-to :from:to:cc:references:in-reply-to:subject:date:message-id :mime-version:content-type; s=20221128; bh=ztRRRZXzhKShMXn8BAN/T bHrln/+bGOx9s3qmxCrs/c=; b=FJrevEVaUNJU1hHAvFzY7fGWYyQKxKUHcKcjf z4v2WeIsD+TqJojpiHuZSFuvJVo/xWCgB70tXl4dEpSHf8GHbfiKnyE6QThczZm5 ZKK71JzXiwigd2vxRItyX3/6uPDIbcrHxc9c8W0mMDAW5GqgbZxisi06KABUYz+E dYtGZG/AT2VBb/MVtG/KkXvsAuBorNaDdc4r73DPRh9xXj/u0ni2fyNUxm6fD+E3 svbN5WFgqfmZha+s6HPZxK8Tf/z0W7HynT3294i5DZHD+m6+t/fq/vCoc58BzxTJ Ueh4MOR0f1VITlnku/+IRjv8q8+myH87d+DSxBjy4iEdyXdsg==
X-TM-AS-GCONF: 00
X-TM-AS-Product-Ver: IMSVA-9.1.0.2090-9.0.0.1006-29464.005
X-TM-AS-Result: No--13.258-10.0-31-10
X-imss-scan-details: No--13.258-10.0-31-10
X-TMASE-Version: IMSVA-9.1.0.2090-9.0.1006-29464.005
X-TMASE-Result: 10--13.258200-10.000000
X-TMASE-MatchedRID: /77LoUQXvQ/aYagUwgwslHFPUrVDm6jtVUB1JKETV5AtferJ/d7Ab5pj +XNqU6N76auJM0Ggx0Bvgi7wnL/fYL5bTFQnR/H9h4Ce12gzEFqyzcnjmIvqX7KeTtOdjMy6RdE +zIIUYmInx5cxKNeBKXO3FRBLy6un3tF9vYxzQ40K3Ma88LL+bjVEnbrqmBw7CuSPuSVW5+5G1Q vheJ9Oe3FuPXR1y1l9TcFRTiQ1a6hdboi6RyakcKJYDeXFTTUT82SgwNf6SK7ILi0hRYnZuV7Ed VZXsXPvz9YXdGTB0gO3xElUZX+x2xV+lXexX99t71Wx2uUbPLdDr8MVm6DK3Vti/oq364XY9Tva dhXG9g3gPqVbzYllURvzEjY4Pdnt7IPLxXyVNZRkGI+vgRTxMFGk5uRH0MzCR6RHdVK85hXaOBW aEqUPGKofXa4f40fCu4BgFjMvXkdA4VPFYKuhbwI6gMblpHUxz8j+bxoiWAyuMXu+rtfqiCXLNM wxp+cYtEKwVHogdvud4kMXmBB5cTqP9GG3SJV14ou+VJXT6vYl3afZehJEWd2Mb1nXqHbB0HI63 c2ctSTizUc+mPOn2R1puVKFgFNeGAdnzrnkM48URSScn+QSXlkMvWAuahr80AUPEgVMzF/HcBri iJvLGVOm2gN+nomsIG4YlbCDECtruV6hT84yE1iwJprBIi4pBYfqsLo1VhokE4RKnd2xfISDw8M VbGZOeFkg0WPgWOh+3BndfXUhXQ==
X-TMASE-SNAP-Result: 1.821001.0001-0-1-22:0,33:0,34:0-0
Message-ID-Hash: ZW2L6HZEG33FUMNKYLE5PIW6J7ICK7J5
X-Message-ID-Hash: ZW2L6HZEG33FUMNKYLE5PIW6J7ICK7J5
X-MailFrom: adrian@olddog.co.uk
X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header
CC: cats@ietf.org
X-Mailman-Version: 3.3.9rc6
Precedence: list
Reply-To: adrian@olddog.co.uk
Subject: [Cats] Re: What's next for CATS? Vienna and beyond
List-Id: "Computing-Aware Traffic Steering (CATS)" <cats.ietf.org>
Archived-At: <https://mailarchive.ietf.org/arch/msg/cats/uT7pJTgr5GTOdVDIFEg4T5zWWV0>
List-Archive: <https://mailarchive.ietf.org/arch/browse/cats>
List-Help: <mailto:cats-request@ietf.org?subject=help>
List-Owner: <mailto:cats-owner@ietf.org>
List-Post: <mailto:cats@ietf.org>
List-Subscribe: <mailto:cats-join@ietf.org>
List-Unsubscribe: <mailto:cats-leave@ietf.org>

Hi Jing,

 

[snip]

 

There are some additional groundwork I-Ds on security, OAM, data models.

a. draft-wang-cats-security-considerations

b. draft-fu-cats-oam-fw

c. draft-yl-cats-data-model

 

[Jing] Do we need to specify a YANG model for the northbound interface here?

 

[AF] I wonder if you could help me understand the positioning of an NBI in the context of figure 2 of draft-ietf-cats-framework.

Which components would implementing the model? Where would it be consumed?

 

[snip]

 

The chairs also think that two protocol applicability documents are maturing

well.

d. draft-yxl-cats-protocols-applicability

e. draft-dunbar-cats-5g-metadata-applicability

 

[Jing] Do we need to include an applicability description for the YANG model here?

 

[AF] Possibly, although maybe not. Where we are talking about how to use existing protocols for enable CATS, the need for an applicability draft is clear. With a new YANG model (specific to CATS) I might expect that draft to describe its own applicability. However, it is possible that many different (including existing) YANG models are needed to manage and operate a CATS system – in that case and applicability draft could be useful.


[snip]

 

People also seem to be interested in discussing "stretch use cases", but the

chairs think that we need to see CATS working before we get too excited

about specialist applicability.

 

[Jing] CATS supports potential extended use cases, and we would appreciate your attention to this area.

 

[AF] Well, of course, everyone should write and discuss the drafts that interest them. I think what the chairs are trying to indicate is that they will be giving priority to the core CATS work and would love to hear about implementations.

 

Best,

Adrian