Subject: Re: [netmod] WG Last Call: draft-ietf-netmod-sub-intf-vlan-model-05

From: Qin Wu <[email-masked]>
Date: Mon, 19 Aug 2019 09:55:19 +0000

I know the LC has ended. But I have a few suggestion to draft-ietf-netmod-sub-intf-vlan-model-05:
1. 
OLD TEXT:
"
     import ieee802-dot1q-types {
      prefix dot1q-type;
     }
"
NEW TEXT:
"
     import ieee802-dot1q-types {
      prefix dot1q-type;
      reference
        "IEEE Std 802.1Q-2018: Virtual Bridged Local Area Networks.";
     }
"
2. Suggest to add IEEE Std 802.1Q-2018 to normative reference.
3. As you described in draft-ietf-netmod-sub-intf-vlan-model,
"
Sub-interface 'eth1.0' is not currently bound to any service and hence
traffic classified to that sub-interface is dropped.
"
Just want to confirm binding eth1.0 to l2vpn service is realized using ac attribute which is leafref to interface in the interface management model.
But as described in RFC8529, binding service to interface is realized by using the following:
"
   augment /if:interfaces/if:interface:
     +--rw bind-ni-name?   -> /network-instances/network-instance/name
   augment /if:interfaces/if:interface/ip:ipv4:
     +--rw bind-ni-name?   -> /network-instances/network-instance/name
   augment /if:interfaces/if:interface/ip:ipv6:
     +--rw bind-ni-name?   -> /network-instances/network-instance/name
"
I am wondering whether this is overdesign in RFC8529.

-Qin
-----邮件原件-----
发件人: netmod [mailto:[email-masked]] 代表 Kent Watsen
发送时间: 2019年7月10日 8:15
收件人: [email-masked]
主题: [netmod] WG Last Call: draft-ietf-netmod-sub-intf-vlan-model-05

All,

This starts a twelve-day working group last call for draft-ietf-netmod-sub-intf-vlan-model-05.

The working group last call ends on July 21 (the day before the NETMOD 105 sessions).  Please send your comments to the working group mailing list.

Positive comments, e.g., "I've reviewed this document and believe it is ready for publication", are welcome!  This is useful and important, even from authors.

Thank you,
NETMOD Chairs
_______________________________________________
netmod mailing list
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https://www.ietf.org/mailman/listinfo/netmod

---

From: Martin Bjorklund <[email-masked]>
Date: Thu, 22 Aug 2019 22:14:53 +0200 (CEST)

Hi,

Here is my (late) review of draft-ietf-netmod-sub-intf-vlan-model-05.

o  1

  The YANG module names are not correct; they are listed as:

      if-l3-vlan.yang - Defines the model for basic classification of
      VLAN tagged traffic to L3 transport services

      flexible-encapsulation.yang - Defines the model for flexible
      classification of Ethernet/VLAN traffic to L2 transport services

   Should be "ietf-if-l3-vlan" and "ietf-flexible-encapsulation".

   Or "ietf-if-l3-vlan" and "ietf-if-flexible-encapsulation".

   But I also wonder if these names should somehow be changed.  What
   is a "l3-vlan"?  And "flexible-encapsulation" sound a bit too
   generic.

o  1.1

  The text says:

   Sub-interface: A sub-interface is a small augmentation of a regular
   interface in the standard YANG module for Interface Management that
   represents a subset of the traffic handled by its parent interface.

  I think the augmentation is the YANG-realization of a sub-interface,
  but it is not what a sub-interface is.  Also, this definition is
  mis-leading; it doesn't mention that a sub-interface has its own
  interface type and is represented as one separate entry in the
  interface list.  I think it is better to import this term from
  draft-ietf-netmod-intf-ext-yang (section 3.6)

o  3

  The text says:

   The L3 Interface VLAN model provides appropriate leaves for
   termination of an 802.1Q VLAN tagged segment to a sub-interface based
   L3 service.

  There is a comment in the YANG model that says the same thing.

  But the YANG model itself augments not only to sub-interface-based
  interface, but also to ethernet-like interfaces.

o  YANG modules

  Both modules lack the IETF Trust Copyright statement.

  We don't list WG Chairs anymore.

  The revision statements should be on the form: "RFC XXXX: <title>"

  Many descriptions are full sentences w/o the ending ".".

  The modules should be indented properly; a starting point can be
  pyang -f yang --yang-line-length 69

o  ietf-if-l3-vlan

  There is a comment:

    /*
     * Matches a single VLAN Id, or a pair of VLAN Ids to classify
     * traffic into an L3 service.
     */

  This should be moved into a description clause.

o  ietf-if-l3-vlan / container dot1q-vlan

  The must statement has:

     count(../../if-cmn:forwarding-mode) = 0

  This can be changed to not(../../if-cmn:forwarding-mode) which is
  more direct imo.

  The must statement's description statement seems to be a
  copy-and-paste error.

o  ietf-if-l3-vlan / container dot1q-vlan

  The descriptions talk about "matching frames" and "classifying
  traffic", but it is not described anywhere how the matching and
  classifying is used.

  (also applies to ietf-flexible-encapsulation)

o  ietf-if-l3-vlan / outer-tag / second-tag

  These names are a bit inconsistent.  The description describes them
  as "outermost tag" and "second outermost tag".  Perhaps use these
  names instead?

  (same names are found in ietf-flexible-encapsulation)

o  ietf-flexible-encapsulation / all features

  The features are described as:

      "This feature indicates whether the network element supports
        specifying flexible rewrite operations";

  Should this be s/whether/that ?

o  ietf-flexible-encapsulation

  There is some descriptive text in comments that should be moved to
  description statements.

o  ietf-flexible-encapsulation

  The descriptions for pop/push are a bit terse.  It seems to assume
  that readers already know what this (from somewhere) is so it
  doesn't need to be described.  If this is intended, perhaps add a
  reference to where this is described.

/martin