Re: [Pce] RtgDir: Early Review of draft-ietf-pce-pcep-flowspec-05.txt - "PCEP Extension for Flow Specification"

"Adrian Farrel" <> Tue, 22 October 2019 18:06 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id 744201208C3; Tue, 22 Oct 2019 11:06:10 -0700 (PDT)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -2.598
X-Spam-Status: No, score=-2.598 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_NONE=0.001] autolearn=ham autolearn_force=no
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id nXyokdl7fjQQ; Tue, 22 Oct 2019 11:06:07 -0700 (PDT)
Received: from ( []) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id C8AF31208CF; Tue, 22 Oct 2019 11:06:03 -0700 (PDT)
Received: from ( []) by (8.14.4/8.14.4) with ESMTP id x9MI5ubS026114; Tue, 22 Oct 2019 19:05:56 +0100
Received: from (unknown []) by IMSVA (Postfix) with ESMTP id E51962203D; Tue, 22 Oct 2019 19:05:55 +0100 (BST)
Received: from (unknown []) by (Postfix) with ESMTPS id CFE062203C; Tue, 22 Oct 2019 19:05:55 +0100 (BST)
Received: from LAPTOPK7AS653V ([]) (authenticated bits=0) by (8.14.4/8.14.4) with ESMTP id x9MI5s3u023839 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 22 Oct 2019 19:05:55 +0100
Reply-To: <>
From: "Adrian Farrel" <>
To: "'Acee Lindem \(acee\)'" <>, "'Routing ADs'" <>, <>
Cc: <>, "'Routing Directorate'" <>
References: <>
In-Reply-To: <>
Date: Tue, 22 Oct 2019 19:05:54 +0100
Organization: Old Dog Consulting
Message-ID: <03f701d58903$597d78c0$0c786a40$>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable
X-Mailer: Microsoft Outlook 16.0
Thread-Index: AQG6E6C8sn35/+ZFZFQe1OZYWuxZSqed1xyA
Content-Language: en-gb
X-TM-AS-Product-Ver: IMSVA-
X-TM-AS-Result: No--4.245-10.0-31-10
X-imss-scan-details: No--4.245-10.0-31-10
X-TMASE-Result: 10--4.245000-10.000000
X-TMASE-MatchedRID: vbSD0OnL8/KWfDtBOz4q22mpWpGzPzJdaMmm586o4gBIXJo+eGm+FIAN SmRMmwdJkQhzdjRVw06isum7bT5AfpsO9o0mINop8eSmTJSmEv0C966cjk9M2CNGK7UC7ElMPaP 83yYyCuSHHWuy6mZy4YKDCK6DSShXUjOzl6DaSNjBjbyj5wYDmpho4qShZLt43FJULPGBSs6KnG /UZgexcA1sT1nh3uMbEDcrP4QSTDOeSiDxtQORDTKVTrGMDe/DcgUuM/TfAYwELMPQNzyJS3lrm OUJ9i8SYu17ep7fd4+ML3vRpxWSz6B6Yk2yF0aOGfTCsR61MuGUUZS7sMHOGE+86maMM3aSO9Zu 2UZqoB5x9iWzeyIAQth+Npcs6iXCjxupKpRZUeIo19GoN4WoGESpWdhkBIOrsl4Rk4lD6eyjxYy RBa/qJeHvPwwcLlxndB0ntd9Tzp7iRhduhvElspgtwixx9AosGtSJtBB2AzcBD2D9l8vvmu33o0 L7ThcmTVFLSRjPVKYzbN4XBnquOlPChrYLF1G/snZsmKfQ27bDvy6lNSRR37IeEe80UWLf5D9sm qVBD9yilnnVDECPd/H7AvsTxZMb7DafdH0+BI7qCyYebl7X7A==
X-TMASE-SNAP-Result: 1.821001.0001-0-1-12:0,22:0,33:0,34:0-0
Archived-At: <>
Subject: Re: [Pce] RtgDir: Early Review of draft-ietf-pce-pcep-flowspec-05.txt - "PCEP Extension for Flow Specification"
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Path Computation Element <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Tue, 22 Oct 2019 18:06:10 -0000

Hi Acee,

Thanks for the review and the kind words.
I believe this document is in WG last call at the moment, so this is not quite so early as an “Early Review” might normally be.

>  I have a question and a few suggestions:
>    1. For the multicast flow filter TLVs, is there some reason why
>       the S-bit and G-bit respectively indicate that the fields are
>       NOT used? In most protocol encodings, a Set bit indicates that
>       a field is used and a Clear bit indicates that it is not used.
>       Also, all zeros has also been used a wildcard specification
>       but I guess you preferred something explicit.

No particular reason for the bit settings that I can remember. It makes the bits fit nicely with the "Reserved" field, but that is not a very telling point. We could change this if there is a good reason to do so.

IIRC the setting of all zeros has a specific meaning in this case and so a different wildcard value was needed.

>    2. For IGPs, we always hyphenate Bit definitions. However, in this
>       specification, the Bit definitions are not hyphenated other
>       than in the IANA section. Being the LSR chair, I'd prefer
>       consistency with the IGP specifications.

I just checked back with RFC 5440 (the PCEP base specification) and there hyphenation is not used.

I have no strong opinion and will let the PCE chairs tell me what to do.

>    3. In most IETF specifications, "headend" is a single compound
>       word. 

Oooh, I hate that 😊
Can we leave it to the RPC to fix as a matter of house style?

>    4. In section 9, could you indicate that the only change is adding
>       the <flowspec-list>? This seems to be the case but it would be
>       good to state it explicitly.

In my working copy.

>   5. I have attached an RFCDIFF of suggested editorial changes.

That was unusually thorough of you. Thanks! All of those nits were spot on and are in my working copy (modulo one s/am/an/).