Subject: [OSPF] Benoit Claise's Discuss on draft-ietf-ospf-encapsulation-cap-06: (with DISCUSS and COMMENT)

From: Benoit Claise <[email-masked]>
Date: Wed, 30 Aug 2017 00:57:21 -0700

Benoit Claise has entered the following ballot position for
draft-ietf-ospf-encapsulation-cap-06: Discuss

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DISCUSS:
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1. I agree with Tim Wicinski's OPS DIR point about IANA.

    The content appears to be fine, but there are some outdated (the biggest
    one is 5226 replaced by 8126), but its the IANA section which appears the
    most confusing.

    7.1 OSPF Router Information (RI) Registry -  appears fine

    7.2 OSPF Tunnel Encapsulation Attribute Sub-TLV Registry

    This one defines the values being defined/allocated from "This Document"
    but in Section 5, each Sub-TLV is defined in other documents, so it's
    totally confusing.

2. It's not clear which of the following sub-TLVs are
required/relevant/interconnected in the Encapsulation Capability TLV

            0    Reserved                                  This document
            1    Encapsulation                             This document
            2    Protocol Type                             This document
            3    Endpoint                                  This document
            4    Color                                     This document
            5    Load-Balancing Block                      This document
            6    IP QoS                                    This document
            7    UDP Destination Port                      This document

The only hint is:

      Value (variable): Zero or more Tunnel Encapsulation Attribute Sub-
      TLVs as defined in Section 5.

Zero? really, what's the point?
Now, from an operational point of view, which sub-TLVs are required/make sense?
Are some sub-TLVs irrelevant without others? Ex: Color without Encapsulation
Could we have multiple identical sub-TLVs? Ex: Color

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COMMENT:
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- Sometimes you use "Encapsulation Capability TLV" (section 3), sometimes "The
Tunnel Encapsulation Type Sub-TLV" I guess that: OLD:

 The Tunnel Encapsulation Type Sub-TLV is structured as follows:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Tunnel Type (2 Octets)     |        Length (2 Octets)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      |                            Sub-TLVs                           |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

NEW:
 The Encapsulation Capability TLV is structured as follows:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Tunnel Type (2 Octets)     |        Length (2 Octets)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      |                            Sub-TLVs                           |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

In section 7.1, should it be?
OLD:
    Value   TLV Name                                  Reference
       -----   ------------------------------------   -------------
       TBD1    Tunnel Capabilities                    This document

NEW:
    Value   TLV Name                                  Reference
       -----   ------------------------------------   -------------
       TBD1    Encapsulation Capabilities             This document

OR:
    Value   TLV Name                                  Reference
       -----   ------------------------------------   -------------
       TBD1    Tunnel Encapsulation Capabilities      This document

- Then there is a discrepancy between Sub-TLVs and Value in the related text

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Tunnel Type (2 Octets)     |        Length (2 Octets)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      |                            Sub-TLVs                           |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Proposal: Sub-TLVs should be replaced by "Tunnel Encapsulation Attribute
Sub-TLVs", and the following text updated:

  Value (variable): Zero or more Tunnel Encapsulation Attribute Sub-
      TLVs as defined in Section 5.

- Then, reading section 5, I see yet another name: "OSPF Tunnel Encapsulation
Attribute Sub-TLVs" Section 7.2.

You should re-read the document to be consistent with your naming convention,
in the text and in the IANA sections.