Re: [netmod] WG LC draft-ietf-netmod-module-tags-02 - 10/2/18 - 10/16/18

Christian Hopps <chopps@chopps.org> Tue, 16 October 2018 22:15 UTC

Return-Path: <chopps@chopps.org>
X-Original-To: netmod@ietfa.amsl.com
Delivered-To: netmod@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id E8053130E52 for <netmod@ietfa.amsl.com>; Tue, 16 Oct 2018 15:15:32 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.9
X-Spam-Level:
X-Spam-Status: No, score=-1.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id nqp2_ucPHqpx for <netmod@ietfa.amsl.com>; Tue, 16 Oct 2018 15:15:31 -0700 (PDT)
Received: from smtp.chopps.org (smtp.chopps.org [54.88.81.56]) by ietfa.amsl.com (Postfix) with ESMTP id 1F58B130E4B for <netmod@ietf.org>; Tue, 16 Oct 2018 15:15:31 -0700 (PDT)
Received: from tops.chopps.org (47-50-69-38.static.klmz.mi.charter.com [47.50.69.38]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by smtp.chopps.org (Postfix) with ESMTPSA id 1F51F6005A; Tue, 16 Oct 2018 22:15:30 +0000 (UTC)
References: <b45d1c39-c2f0-bcaf-61a4-9822ac04725a@bogus.com> <20181002203031.pcdclhq7vb5tohrj@anna.jacobs.jacobs-university.de> <57BCB4D8-D82F-43C9-8D05-2F52A174F37C@chopps.org> <20181016130829.3jnbnxyb5vjlogih@anna.jacobs.jacobs-university.de> <CABCOCHTZ6Vj+5WxmAXQLVCEQ3AP95RbYtvCqh0PtsuUdaANM8A@mail.gmail.com> <sa64ldl8ypz.fsf@chopps.org> <CABCOCHQNrdNhAqEx_KMToJw6kRHCWAP2e10cBTH8r_b-MZYSnQ@mail.gmail.com>
User-agent: mu4e 1.0; emacs 26.1
From: Christian Hopps <chopps@chopps.org>
To: Andy Bierman <andy@yumaworks.com>
Cc: Christian Hopps <chopps@chopps.org>, Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>, joel jaeggli <joelja@bogus.com>, NETMOD Working Group <netmod@ietf.org>
In-reply-to: <CABCOCHQNrdNhAqEx_KMToJw6kRHCWAP2e10cBTH8r_b-MZYSnQ@mail.gmail.com>
Date: Tue, 16 Oct 2018 18:15:29 -0400
Message-ID: <sa6zhvd7d32.fsf@chopps.org>
MIME-Version: 1.0
Content-Type: text/plain; format=flowed
Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/l4XQrA33YEljwzp90OOFxLQMm8Y>
Subject: Re: [netmod] WG LC draft-ietf-netmod-module-tags-02 - 10/2/18 - 10/16/18
X-BeenThere: netmod@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: NETMOD WG list <netmod.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/netmod>, <mailto:netmod-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/netmod/>
List-Post: <mailto:netmod@ietf.org>
List-Help: <mailto:netmod-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/netmod>, <mailto:netmod-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 16 Oct 2018 22:15:33 -0000

Andy Bierman <andy@yumaworks.com> writes:
>
> This draft needs to define the module-tag encoding wrt/
>    - valid characters (e.g., some subset of UTF-8)
>    - min/max length (e.g., implementation MUST support at least 64 chars
> and can support larger)

I'm looking for suggestions on how to do this subset. We had intended to allow for as wide as possible content; however, I think disallowing tabs, newlines, carriage returns is more than reasonable. Has a type like this already been standardized or is there an example available somewhere?

> Section 3 (Tag Prefixes) seems to imply that all modules tags follow a
> structure to specify the naming authority.
>
> According to the YANG module, the data type is a plain string, which
> includes lots of
> problematic chars and zero-length strings.
>
> Does the string "routing" match "ietf:routing" or "vendor:routing"? How
> about "routing:bgp"?

No. Do we need to state that non-matching strings don't match?

> Is the char ":" allowed in a tag?

Yes, why not?

> Is "vendor::::::::" a valid tag?

Again why not?

The only thing the draft talks about are standard prefixes. Why should a standard enumerate a subset of the unbounded set of things it isn't standardizing? This seems more confusing (why was X included as OK but not Y) than just sticking to what it *is* standardizing.

Perhaps a bit of text saying more explicitly that only the prefix is restricted would help though?

> IMO this draft does not need to define any specific module-tag content but
> it does need to define
> in precise terms how a protocol encodes a module-tag and how a module-tag
> match is determined.

We considered leaving out all the predefined tags, but conversely we also thought it would be useful to establish a base set. We went with the latter obviously. Perhaps it just needs to be trimmed down more?

Thanks,
Chris.

>
>
> Thanks,
>> Chris.
>>
>
> Andy