Bert,
Many thanks for your comments.
More inlined.
Bruno
-----Message d'origine-----
De : Bert Wijnen - IETF [mailto:bertietf(_at_)bwijnen(_dot_)net]
Envoyé : dimanche 27 avril 2008 11:43
À : ietf(_at_)ietf(_dot_)org; ina(_at_)juniper(_dot_)net; LE ROUX Jean-Louis
RD-SIRP-LAN; DECRAENE Bruno RD-CORE-ISS
Objet : FW: OPS-DIR review for: draft-ietf-mpls-ldp-interarea-03.txt
Forwarding to IETF wide list and authors/editors
Bert Wijnen
-----Oorspronkelijk bericht-----
Van: Bert Wijnen - IETF [mailto:bertietf(_at_)bwijnen(_dot_)net]
Verzonden: donderdag 24 april 2008 13:55
Aan: ops-dir(_at_)ietf(_dot_)org
Onderwerp: OPS-DIR review for: draft-ietf-mpls-ldp-interarea-03.txt
I reveied this document for the OPS Directorate
In general, I think the document is ready for publication.
In sect 7.1 I read:
For the successful establishment of end-to-end MPLS LSPs whose FEC
are aggregated in the RIB, this specification must be implemented on
all LSRs in all areas where IP aggregation is used. If an LSR on the
path does not support this procedure, then the LSP initiated on the
egress LSR stops at this non compliant LSR. There are no other
adverse effects.
I think/hope (but it would be good to see this confirmed) that this does
not mean that all LSRs in the set of IGPs that are involved need to be
upgraded with the new protocol at exactly the same time.
The way I understand it, one can upgrade the LSRs at different times,
but should only activate this new mechnaism once all LSRs have
ineeded been upgraded with the new capability.
You're right: all LSRs do not need to be upgraded at the same time:
- deployment in each IGP (area) is independent
- LSRs can be upgraded at any time in any order,
- This new mechanism can be activated on the LSR at any time in any order,
(upgrade and activation can be done at same step if it's considered easier)
- Then, if the FEC/LSP were used, we need a non disruptive deployment:
(As a reminder, the ABRs used to leak all specific prefixes in the IGP
area.)
The ABRs can advertise the (new) aggregate prefix at any time and any
order.
However, the specific prefixes in the IGP area should only be withdrawn
(by the ABRs) once all the LSR of this IGP area have been upgraded. (Otherwise
"If an LSR on the path does not support this procedure, then the LSP initiated
on the egress LSR stops at this non compliant LSR.")
Do you think this should be clarified in the document?
Nits:
Thanks.
All corrections are done and will appear in the next revision.
- There are several/many acronyms in this document that never get
expanded. It is good pratice to always expand an acronym when
it is used for the first time.
- Abstract
To facilitate the establishment of Label Switched Paths (LSP) that
would span multiple IGP areas in a given Autonomous System (AS), this
document proposes a new optional label mapping procedure for the
Label Distribution Protocol (LDP).
s/proposes/describes/ (at least once this comes out as RFC, right?)
- need to add citation to RFC2119 in section 1.
And add a normative reference for RFC2119.
- 2nd para section 4:
To set up the required MPLS LSPs between PEs in different IGP areas,
services providers have currently three solutions: LDP with IGP route
s/services/service/ I think.
- consistency: I see
Service providers
service providers
Service Providers
I suggest to use consistent capitalization
- 1st para sect 5:
This document defines a new label mapping procedure for [LDP]. It is
applicable to IPv4 and IPv6 prefix FEC elements (addresses families 1
and 2 as per [ASSIGNED_AF]). It MUST be possible to activate / ^M
I believe it is "address families" (or maybe "addressing families") but
not "addresses families". So I would: s/addresses/address/
- sect 5, I see
longest match label mapping procedure
longest match Label Mapping Procedure
"Longest Match" label mapping procedure
longest match procedure
you might want to be a bit moire consistent
- Section 5:
- next-hop change when an existing prefix have new next hop
following a routing change.
s/have new/has a new/ ??
- When the next-hop of a RIB prefix change, the LSR must change
change the first "change": s/change/changes/ or so I think.
- 2nd para section 7.2
In case of failure of the egress LER node, given that the IGP
aggregates IP route on ABRs, the routing convergence behavior is
changed compared to [LDP]. As the IGP does not carry specifics
prefixes outside of the egress area, the IGP will not propagate the
s/specifics prefices/specific prefixes/ (or so I think)
- Last para sect 7.2
For all others failures
s/others/other/
Bert Wijnen
-----Oorspronkelijk bericht-----
Van: Seely, Ted A [CTO] [mailto:Ted(_dot_)A(_dot_)Seely(_at_)sprint(_dot_)com]
Verzonden: donderdag 17 april 2008 13:42
Aan: Bert Wijnen
Onderwerp: OPS DIR Review Request
Hello Bert,
As a member of the Operations Directorate you are being asked to review the
following IESG work item for it¹s operational impact.
IETF Last Call:
http://www.ietf.org/internet-drafts/draft-ietf-mpls-ldp-interarea-03.txt
BTW - This is a very short draft.
If possible please provide comments and review to the Ops-dir mailing list
(ops-dir(_at_)ietf(_dot_)org), preferably before next Wednesday if possible.
Thank you Bert,
Ted
_______________________________________________
IETF mailing list
IETF(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/ietf