Subject: Review: draft-ietf-ccamp-gmpls-overlay-04.txt

From: Alex Zinin <[email-masked]>
Date: Mon, 21 Jun 2004 15:38:21 -0700

I'm starting AD-review for this document.

Dimitri, Loa, please review it for RTG-DIR.

   Generalized Multiprotocol Label Switching (GMPLS) defines both
   routing and signaling protocols for the creation of Label Switched
   Paths (LSPs) in various transport technologies.  These protocols can
   be used to support a number of deployment scenarios.  This memo
   addresses the application of GMPLS to the overlay model.

Document is available at: http://www.ietf.org/internet-drafts/draft-ietf-ccamp-gmpls-overlay-04.txt

-- 
Alex
http://www.psg.com/~zinin

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From: [email-masked]
Date: Sat, 26 Jun 2004 03:06:02 +0200

hi alex, find here below my review of this document

o) Technical Comments (minor):

1. Introduction mentions "However, one possible means is
    using a forwarding adjacency as described in [MPLS-HIER]."

-> but forwarding adjacencies are by definitions related to the peer
    model (also, [MPLS-HIER] does not refer to this "hierarchical TE
    link" - see end Section 4 of [MPLS-HIER])

2. Section 3.2: "If the route is not viable, then a PathErr message with
    an error code and value of 24,5 - "No route available toward
    destination" should be returned."

-> "viability" should probably be further detailed

3. Section 3.3: "In order to support explicit label control and full
    identification of the egress link an ingress edge-node may include an
    ERO that consists of only the last hop."

-> unclear why *only* the last hop can be included in such ERO (why this
    sentence does not only determine the behaviour at the last hop being
    the egress core-node)

4. Section 6.2: mapping 2 is not allowed (independently of the presence
    of the Path_State_Removed_Flag from the receiving PathErr) since
    PathErr propagation rule is disrupted as far as the proposed text
    reads

o) Editorial Comments:

1. Spell out the acronyms in the document title (GMPLS, UNI, etc.)

2. in Abstract: "Generalized Multiprotocol Label Switching (GMPLS)
    defines both routing and signaling protocols for the creation of
    Label Switched Paths (LSPs) in various transport technologies."

-> transport technologies might not be the most appropriated in the IETF
    context - suggestion replace it by "switching"

3. Introduction 1): "The four boxes around the edge marked "Overlay
    Network" represent four islands of a single network overlaid
    network"

-> not sure the last part of this sentence is not mispelled

4. Section 3) "If a core-node rejects a Path message due to the presence
    of an ERO it SHOULD return an PathErr message with an error code of
    "Unknown object class" toward the sender. This causes the path setup
    to fail."

-> should point to the RFC 3209 section: "4.3.7. Non-support of the
    Explicit Route Object" as procedures are apparently equivalent

5. Section 5) " Core-nodes may send Notification messages to edge-nodes
    which have included the NOTIFY_REQUEST object."

-> suggested: "Core-nodes MAY send Notify messages to edge-nodes which
    have included the NOTIFY_REQUEST object."

6. Section 5) "In either of the above cases, the a core-node SHOULD NOT
    send Notify messages to the edge-node.

-> edit: "the a"

7. Section 5) "In this case, when NOTIFY messages are received, they
    MAY be selectively (based on local policy) forwarded to the edge-
    node."

-> edit: NOTIFY -> Notify

8. Section 6.1) "An ingress core-node receiving a PathTear without
    having first seen an ADMIN_STATUS object informing it that the
    connection is about to be deleted MAY pause the PathTear and first
    send a Path message with an ADMIN_STATUS object to inform all
    downstream LSRs that the connection is about to be deleted."

-> first time in this document that the term "LSR" appears

9. Update the Informative Reference section with latest version of the
    referenced document

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-- 
Papadimitriou Dimitri
E-mail : [email-masked]
E-mail : [email-masked]
Webpage: http://psg.com/~dpapadimitriou/
Address: Fr. Wellesplein 1, B-2018 Antwerpen, Belgium
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