[mpls] Re: Working Group Adoption Poll on draft-mb-mpls-ioam-dex

[Haoyu Song <[e-mail]>]

WG,
I don’t think this reverse can change anything. Many fields specified in RFC9326 are still changed and constrained. Note that RFC9326 is extensible. In the future, more flags can be specified to indicate more optional fields (e.g., RFC9630 specifies one more optional field to support multicast).  The limitation on the leading bit and S bit in the MPLS label will almost surely cause compatibility troubles in the naming and encoding.  So, I still object the adoption of this draft.

Best regards,
Haoyu

From: Greg Mirsky <[e-mail]>
Sent: Monday, October 21, 2024 7:36 AM
To: [e-mail]
Cc: [e-mail]; [e-mail]; [e-mail]
Subject: [mpls] Re: Working Group Adoption Poll on draft-mb-mpls-ioam-dex

Dear All,
a short update on the new version of the draft. The authors discussed questions about the format of optional fields (Flow ID and Sequence Number). The new version proposes the following format:

    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

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   |1|         Namespace-ID          |    Resv   |S|     Flags     |

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   |1|            IOAM-Trace-Type-MNA            |S|O|R| Ext-Flags |

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   |                     Flow ID MNA (Optional)                    |

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   |                 Sequence Number MNA (Optional)                |

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



         Figure 1: IOAM Direct Export Option Type Format in an MPLS

                          Network Action Framework

and defined as following:

   *  Flow ID MNA is an optional four-octet field.  The semantics of the

      Flow ID MNA field is as of the Flow ID field defined in

      Section 3.2 of [RFC9326].  The most significant bit MUST be set to

      1.  Bit 23 MUST be set according to the definition of Bottom of

      Stack field in [RFC3032].



   *  Sequence Number MNA is an optional four-octet field.  The

      semantics of the Sequence Number MNA field is as of the Sequence

      Number field defined in Section 3.2 of [RFC9326].  The most

      significant bit MUST be set to 1.  Bit 23 MUST be set according to

      the definition of Bottom of Stack field in [RFC3032].  In MPLS

      network environments where a label stack information is used for

      load-balancing flows, the 19-bit-long part of the Sequence Number

      MNA, starting from the Bit 1 position of the LSE, MUST remain

      immutable for a particular packet flow that the value of the Flow

      ID MNA field identifies.  In MPLS networks, where other load-

      balancing techniques are used, all bits of the Sequence Number MNA

      field can be variated.



Your questions and comments are always welcome and greatly appreciated.



Regards,

Greg (on behalf of the authors)

On Mon, Oct 7, 2024 at 8:47 AM <[e-mail]<mailto:[e-mail]>> wrote:
Dear WG,

This email starts a two-week poll on adopting draft-mb-mpls-ioam-dex as a MPLS working group document.

Please send your comments (support/not support) to the MPLS working group mailing list ([e-mail]<mailto:[e-mail]>).
Please give a technical motivation for your support/not support, especially if you think that the document
should not be adopted as a working group document.

Currently, there is no IPR disclosure against this document.  All the authors/contributors have stated on
the MPLS WG mailing list that they are unaware of any undisclosed IPRs that relates to this document.

This working group adoption poll ends October 22nd, 2024.

Regards,

Nic (as MPLS WG Co-chair)