Subject: [Lsr] Benjamin Kaduk's No Objection on draft-ietf-lsr-yang-isis-reverse-metric-04: (with COMMENT)

From: Benjamin Kaduk via Datatracker <[email-masked]>
Date: Sat, 27 Nov 2021 15:06:56 -0800

Benjamin Kaduk has entered the following ballot position for
draft-ietf-lsr-yang-isis-reverse-metric-04: No Objection

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COMMENT:
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Thanks for the simple and easy-to-read document!
My comments are pretty minor.

Section 2.2

     grouping reverse-metric-if-config-data {
       description "IS-IS reverse metric config data.";
       container reverse-metric {
         description "IS-IS reverse metric data.";
         uses reverse-metric-data;
         leaf exclude-te-metric {
           type boolean;
           default false;
           description
             "If true and there is a TE metric defined for this
              interface then do not send the TE metric sub-TLV in the
              reverse metric TLV.";
           reference "RFC8500, Section 3.5";
         }
       }
     }

     grouping tlv16-reverse-metric {
       description "IS-IS reverse metric TLV data.";
       container reverse-metric {
         description "IS-IS reverse metric TLV data.";
         uses reverse-metric-data;
         leaf te-metric {
           type uint32;
           description
             "The TE metric value from the sub-TLV if present.";
           reference "RFC8500, Section 3.5";
         }
       }
     }

Please confirm that Section 3.5 of RFC 8500 is the right reference for
both of these; I didn't really see much there that lined up well with
these descriptions.

       container reverse-metric {
         description "Announce a reverse metric to neighbors.";
         uses reverse-metric-if-config-data;
         container level-1 {
           description
             "Announce a reverse metric to level-1 neighbors.";
           uses reverse-metric-if-config-data;
         }
         container level-2 {
           description
             "Announce a reverse metric to level-2 neighbors.";
           uses reverse-metric-if-config-data;
         }
       }

Are the interactions between the toplevel
"reverse-metric-if-config-data" and the per-level uses of that grouping
adequately specified by the core draft-ietf-isis-yang-isis-cfg such that
we don't need to repeat them here?  (I think it probably is.)

Section 4

   These are the subtrees and data nodes and their sensitivity/
   vulnerability:

I think the intent of the security considerations template is that we
specifically talk about what bad things would happen if some
unauthorized entity was writing values to the ("config true") nodes, or
reading values from the ("config false") nodes.  The current text here
seems to just be listing the nodes without saying what happens if
they're misconfigured or the contents are leaked to an unauthorized
party.  (On first glance, it seems like the security considerations of
RFC 8500 basically cover everything that we would need to say.  It's
short, so we could repeat the content, or we could say that these YANG
nodes correspond directly to the RFC 8500 functionality and the
considerations of the functionality are described in RFC 8500.)

Section 5

The core NETCONF/RESTCONF RFCs may not need to be classified as
normative (we only reference them from the security considerations
boilerplate), but there's not much harm in leaving them here.

Appendix A

Thank you for including the examples!