Subject: TSVDIR Review for draft-ietf-mpls-ip-options-05

From: "James M. Polk" <[email-masked]>
Date: Thu, 09 Dec 2010 18:15:04 -0600

I've reviewed this document as part of the transport area 
directorate's ongoing effort to review key IETF documents. These 
comments were written primarily for the transport area directors, but 
are copied to the document's authors for their information and to 
allow them to address any issues raised. The authors should consider 
this review together with any other last-call comments they receive. 
Please always CC <mailto:[email-masked]>[email-masked] if you 
reply to or forward this review.

Summary:
This is a well written, concise and needed modification to MPLS.

That said, I don't understand why the 1st minor issue below is 
present. Recommend (fairly strongly) adding the

     "Document Updates: RFC 3031, RFC 3032"

as mentioned below on this first page of this RFC to be.

Transport Issues:
There are no issues

minor issues:
- S2 "Motivation", last sentence is

   "We believe that this document adds
   details that have not been fully addressed in [RFC3031] and [RFC3032]
   as well as complements [RFC3270], [RFC3443] and [RFC4950]. "

I find it surprising that this document does not formally update 3031 
and 3032, given that it is mandatory to implement, optional to 
invoke. ISTM, as an outsider to MPLS, this would in fact be the case 
given the impact of/to IP stacks not adhering to this proposed standard.

- Section 5.2 is about Router Alert Options, and states "At the time 
of this writing ...". I wonder if this subsection is valid, or needs 
another review against this IntArea ID
http://tools.ietf.org/html/draft-ietf-intarea-router-alert-considerations-02
to still be valid in a month or two once the IntArea ID (currently in 
WGLC) is processed by the IESG and RFC-Editor?

IMO - these two docs are progressing near enough to each other to 
each consider what the other says - with or without a normative or 
informative reference in either or both docs to the other.

nits:
- I'm surprised to see the Abstract on page 2. I thought we 
collectively fixed the case in which the Abstract can be on any page 
other than page 1.

- at the page Footer, in the middle of the line, there isn't a "short 
document name" - which has been there on all previous well formed IDs 
and RFCs that I have seen (which of course is not all of them). It is 
recommended the authors pick a short form name for the subject of 
this doc for this location, such as

      LER Header Option Behaviors

- S3, 4th para, second to last sentence is:

   "First a downstream LSR may
   have not have sufficient IP routing information to forward the packet
   resulting in packet loss. "

recommend removing the first instance of "have". The sentence reads 
better without it.

- S3, 4th para, last two sentences
list a "First" and a "Second" reason correctly, but are missing 
required commas after each word (i.e., "First, ...", and "Second, ..." )

- S3, 5th para, 1st sentence is lacking commas here:

   "...FEC, yet are forwarded
   into an IP/MPLS network without being MPLS-encapsulated,
    present..."

- S5.1, last bullet has this:

   "...MPLS encapsulation at a ingress LER ..."
                           ^^^^^
s/a/an

James

---

From: "David Smith (djsmith)" <[email-masked]>
Date: Wed, 15 Dec 2010 14:23:19 -0600

Hi James,

Many thanks for the review & comments. We will incorporate them into -06
which we'll post soon. See our feedback inline below as well [djsmith]. 

Regards, 

/dave

-----Original Message-----
From: James Polk (jmpolk) 
Sent: Thursday, December 09, 2010 7:15 PM
To: [email-masked]; John Mullooly (jmullool); [email-masked]; David
Smith (djsmith); [email-masked]
Cc: [email-masked]; [email-masked]
Subject: TSVDIR Review for draft-ietf-mpls-ip-options-05

I've reviewed this document as part of the transport area directorate's
ongoing effort to review key IETF documents. These comments were written
primarily for the transport area directors, but are copied to the
document's authors for their information and to allow them to address
any issues raised. The authors should consider this review together with
any other last-call comments they receive. 
Please always CC <mailto:[email-masked]>[email-masked] if you reply
to or forward this review.

Summary:

That said, I don't understand why the 1st minor issue below is present.
Recommend (fairly strongly) adding the

[djsmith] ack, changed to ID updates RFC 3031 (but not RFC 3032).
Changed ID header and Motivation text per below.

Transport Issues:
There are no issues

minor issues:

I find it surprising that this document does not formally update 3031
and 3032, given that it is mandatory to implement, optional to invoke.
ISTM, as an outsider to MPLS, this would in fact be the case given the
impact of/to IP stacks not adhering to this proposed standard.

[djsmith] ack, changed to ID updates RFC 3031 (but not RFC 3032).
Changed ID header and Motivation text "We believe that this document
adds details that have
not been fully addressed in [RFC3031] and [RFC3032], and that the
methods presented in this document update [RFC3031] as well as
complement [RFC3270], [RFC3443] and [RFC4950]."

- Section 5.2 is about Router Alert Options, and states "At the time of
this writing ...". I wonder if this subsection is valid, or needs
another review against this IntArea ID
http://tools.ietf.org/html/draft-ietf-intarea-router-alert-consideration
s-02
to still be valid in a month or two once the IntArea ID (currently in
WGLC) is processed by the IESG and RFC-Editor?

IMO - these two docs are progressing near enough to each other to each
consider what the other says - with or without a normative or
informative reference in either or both docs to the other.

[djsmith] Note, the text relating to "at the time of this writing" is
referring to the (MPLS) Router Alert Label not the (IP) Router Alert
Option. Hence, this section remains valid given no existing standard for
Router Alert Label imposition. This ID specifies that a IP RAO cannot
influence imposition of a RAL (Router Alert Label). So we've kept this
section as is. 

nits:
- I'm surprised to see the Abstract on page 2. I thought we collectively
fixed the case in which the Abstract can be on any page other than page
1.

[djsmith] ack, changed. I think you meant Abstract _cannot_ be on any
page other than page 1.

- at the page Footer, in the middle of the line, there isn't a "short
document name" - which has been there on all previous well formed IDs
and RFCs that I have seen (which of course is not all of them). It is
recommended the authors pick a short form name for the subject of this
doc for this location, such as

[djsmith] ack, changed. 

[djsmith] ack, changed. 

- S3, 4th para, last two sentences
list a "First" and a "Second" reason correctly, but are missing required
commas after each word (i.e., "First, ...", and "Second, ..." )

[djsmith] ack, changed. 

[djsmith] ack, changed. 

[djsmith] ack, changed. 

James