IETF Logo Mail Archive

Re: [MMUSIC] draft-ietf-mmusic-rfc4566bis-10: can attributes have a null value

"Ali C. Begen (abegen)" <abegen@cisco.com> Tue, 05 August 2014 14:41 UTC

Return-Path: <abegen@cisco.com>
X-Original-To: mmusic@ietfa.amsl.com
Delivered-To: mmusic@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id C90831B2836 for <mmusic@ietfa.amsl.com>; Tue, 5 Aug 2014 07:41:58 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -14.502
X-Spam-Level:
X-Spam-Status: No, score=-14.502 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_HI=-5, RP_MATCHES_RCVD=-0.001, SPF_PASS=-0.001, USER_IN_DEF_DKIM_WL=-7.5] autolearn=ham
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 J7JzEIhSXTEW for <mmusic@ietfa.amsl.com>; Tue, 5 Aug 2014 07:41:54 -0700 (PDT)
Received: from rcdn-iport-6.cisco.com (rcdn-iport-6.cisco.com [173.37.86.77]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id BF9CE1B282F for <mmusic@ietf.org>; Tue, 5 Aug 2014 07:41:54 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=1191; q=dns/txt; s=iport; t=1407249714; x=1408459314; h=from:to:cc:subject:date:message-id:references: in-reply-to:content-id:content-transfer-encoding: mime-version; bh=YELDdBlNAsOCAC2/UGoSmttj+rzSNjH9fck4Yru04v0=; b=iRxEPbsPyZuo140cLDjGUUoyPQN9Iz324W3mkKhDwIlvdZoZaia6TPsn +CvGfVQaeJLPNZ8PIV4/8qyuKytYpAB+xjAByCKmLRp3gFaisDM7tn1ZV EHDgwjLV3QpRIFW1ddMOl/e6l5VWm3ykLxjO859UQwQXwLw4WsASyXQRk k=;
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: AjgFAM3s4FOtJA2I/2dsb2JhbABbgmojUlcEy2UKhnVTAYETFneEBAEBAwEBAQE3NAsFCwIBCDYQJwslAQEEDgWIOggBDMM2EwSPGTMHgy+BHAWOe40SlGGDTWyBRg
X-IronPort-AV: E=Sophos;i="5.01,805,1400025600"; d="scan'208";a="345242076"
Received: from alln-core-3.cisco.com ([173.36.13.136]) by rcdn-iport-6.cisco.com with ESMTP; 05 Aug 2014 14:41:48 +0000
Received: from xhc-aln-x11.cisco.com (xhc-aln-x11.cisco.com [173.36.12.85]) by alln-core-3.cisco.com (8.14.5/8.14.5) with ESMTP id s75Efm7a024219 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL); Tue, 5 Aug 2014 14:41:48 GMT
Received: from xmb-aln-x01.cisco.com ([fe80::747b:83e1:9755:d453]) by xhc-aln-x11.cisco.com ([173.36.12.85]) with mapi id 14.03.0123.003; Tue, 5 Aug 2014 09:41:48 -0500
From: "Ali C. Begen (abegen)" <abegen@cisco.com>
To: Brett Tate <brett@broadsoft.com>
Thread-Topic: [MMUSIC] draft-ietf-mmusic-rfc4566bis-10: can attributes have a null value
Thread-Index: Ac+wtz8/SRlEsRzHTeyKczkmwewwRAALgxgA
Date: Tue, 5 Aug 2014 14:41:48 +0000
Message-ID: <B2202240-B887-4E76-8D36-C3C15A95846F@cisco.com>
References: <b0f1449ce327d51a1a6e947df246533f@mail.gmail.com>
In-Reply-To: <b0f1449ce327d51a1a6e947df246533f@mail.gmail.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [10.61.110.253]
Content-Type: text/plain; charset="us-ascii"
Content-ID: <4BA7F1BDC33261458045E1092082873C@emea.cisco.com>
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
Archived-At: http://mailarchive.ietf.org/arch/msg/mmusic/fsMC-EunVc5ssNHlqSLhm11iqxM
Cc: "mmusic@ietf.org" <mmusic@ietf.org>
Subject: Re: [MMUSIC] draft-ietf-mmusic-rfc4566bis-10: can attributes have a null value
X-BeenThere: mmusic@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Multiparty Multimedia Session Control Working Group <mmusic.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mmusic>, <mailto:mmusic-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/mmusic/>
List-Post: <mailto:mmusic@ietf.org>
List-Help: <mailto:mmusic-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mmusic>, <mailto:mmusic-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 05 Aug 2014 14:41:59 -0000

On Aug 5, 2014, at 5:12 PM, Brett Tate <brett@broadsoft.com> wrote:

> Hi,
> 
> Draft-ietf-mmusic-rfc4566bis-10 section 5.13 discusses two formats of
> attribute fields.  However, it doesn't appear to clearly indicate the
> validity/invalidity of colon without a value.

It says there are two forms. since "a=<attribute>:" is not listed as a form, I guess it simply means it is not valid usage.

> 
> Is an attribute such as "a=rtcp-xr:" valid?  

Not based on my knowledge.

> For instance, RFC 3611
> indicates that it is valid; however errata 3795 indicates that it
> potentially shouldn't be valid.

I am not sure why that errate is not verified. To me, 3611 has an abnf syntax error that should be fixed.

> 
> Should draft-ietf-mmusic-rfc4566bis-10 section 5.13 be updated to clarify
> the topic?

We can add a sentence to ban such a usage but now I wonder whether they have been attributes defined in that form in the past. Is anyone aware of any?

-acbegen

> 
> Thanks,
> Brett
> 
> _______________________________________________
> mmusic mailing list
> mmusic@ietf.org
> https://www.ietf.org/mailman/listinfo/mmusic

v2.8.10 | Report a Bug | By Email