Re: [Lime] Alia Atlas' Discuss on draft-ietf-lime-yang-connectionless-oam-14: (with DISCUSS and COMMENT)

[Qin Wu <[e-mail]>]

Thank Alia for valuable comments and Thanks Benoit for clarification,
Please see my reply inline below.
发件人: Benoit Claise [mailto:[e-mail]]
发送时间: 2017年10月26日 10:27
收件人: Alia Atlas; The IESG
抄送: Ron Bonica; [e-mail]; [e-mail]; [e-mail]; [e-mail]
主题: Re: Alia Atlas' Discuss on draft-ietf-lime-yang-connectionless-oam-14: (with DISCUSS and COMMENT)

Hi Alia,

Some answers below.
I let the authors chime in.

Alia Atlas has entered the following ballot position for

draft-ietf-lime-yang-connectionless-oam-14: Discuss



When responding, please keep the subject line intact and reply to all

email addresses included in the To and CC lines. (Feel free to cut this

introductory paragraph, however.)





Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html

for more information about IESG DISCUSS and COMMENT positions.





The document, along with other ballot positions, can be found here:

https://datatracker.ietf.org/doc/draft-ietf-lime-yang-connectionless-oam/







----------------------------------------------------------------------

DISCUSS:

----------------------------------------------------------------------



Thank you for your work on this document.  I have a number of serious concerns

- but they all amount to fixing up your references and slight restructuring

for clarity and reuse.



1) In Sec 3.1, the reference is system-id to represent the device or

node.[I-D.ietf-spring-sr-yang] I believe that should be "typedef router-id {

       type yang:dotted-quad;

       description

         "A 32-bit number in the dotted quad format assigned to each

          router. This number uniquely identifies the router within

          an Autonomous System.";

     }"

from draft-ietf-rtgwg-routing-types.

Certainly "[I-D.ietf-spring-sr-yang]" is NOT an informative reference with such

a dependency.



I see that this document actually redefines router-id, instead of using it as

part of the included import from

 import ietf-routing-types {

   prefix rt;

  }
This was part of my AD review (on the LIME mailing list) in August.
- Cut and paste the typedefs from https://datatracker.ietf.org/doc/draft-ietf-rtgwg-routing-types/

    typedef router-id {

    typedef ipv4-multicast-group-address

    typedef ipv6-multicast-group-address {

        ...
If published fast enough, you should import the types from https://datatracker.ietf.org/doc/draft-ietf-rtgwg-routing-types/
I'm happy to see that draft-ietf-rtgwg-routing-types is finally approved.
So authors, it's time to import the router-id

[Qin]: My fault, we thought we have addressed comments raised by AD Review but forget to clean up router-id we ourselves defined,
We will fix this.



On p.27, I see "leaf system-id {

          type rt:router-id;

          description

            "System ID assigned to this node.";

        }"

so it is using the routing-yang-types, but renaming it as system-id, there.

Consistency isn't just the hobgoblin of little minds - it's actually useful.
Make sense to me.


[Qin]: Good catch, will fix this, thanks.



In choice to-location, again "case system-id {

          leaf system-id-location {

            type router-id;

            description

              "System id location";

          }

          description

            "System ID";"

using the locally defined router-id and renaming it instead of using

rt:router-id.



[Qin]: Will fix this, thanks.



2) On p. 13 & 14, there are many identities associated with time and

time-stamps.  I cannot believe that the best way to handle these is by having

them as part of an OAM model!   At a minimum, they should be defined as a

separate module and then included, even if it is in the same draft.  Then they

will be available for reuse elsewhere.



[Qin]:Umm, good suggestion, I prefer to keep it in the same draft. Thanks.



3) This is extending [I-D.ietf-i2rs-yang-network-topo] - I do not believe this

should be merely an informative reference.

Note sure what you mean:



 augment "/nd:networks/nd:network/nd:node" {

    description

      "Augment test points of connectionless oam.";

        uses test-point-locations;

  }

[Qin]: We can make description more clear with the following changes：

NEW TEXT:

“

augment "/nd:networks/nd:network/nd:node" {

    description

      " augments /networks/network/node path defined in the ietf-

   network module (I-D.ietf-i2rs-yang-network-topo) with test-point-

   locations grouping”

  }



”
https://www.yangcatalog.org/yang-search/impact_analysis.php?modules[]=ietf-connectionless-oam&recurse=0&rfcs=1&show_subm=1&show_dir=dependencies






4) I cannot tell if I-D.ietf-rtgwg-ni-model is informative or normative; it is

not referenced in the draft - though there are fields that are labeled NI

without adequate description.
https://www.yangcatalog.org/yang-search/impact_analysis.php?modules[]=ietf-connectionless-oam&recurse=0&rfcs=1&show_subm=1&show_dir=dependencies

The generic question is: if I import a YANG module from draft D, then D should be a normative reference.






5) [I-D.ietf-rtgwg-routing-types] is not an informative reference.  Its module

is imported and used.  It must be normative.
Yes.

Regards, Benoit






6) [I-D.ietf-spring-sr-yang] is listed as an informative reference, but if it

were actually used as described, it would need to be normative. Instead, I

believe this can be removed as a reference.





----------------------------------------------------------------------

COMMENT:

----------------------------------------------------------------------



a) Sec 3.8: It is unfortunate that the cc-session-statistics-data structure is

not a list of {traffic type, cc-session-statistics} instead of hardcoded

members for IPv4 and IPv6 traffic only.  While it can still be extended for

additional traffic types, the naming may be inconsistent and there's no

requirement that the contents are cc-session-statistics.



[Qin]: Good suggestion, the proposed change could be:

“

  container cc-session-statistics-data {

    if-feature "continuity-check";

    config false;

    list cc-session-statistics {

       key type;

       leaf type {

        type identityref {

         base traffic-type;

        }

        description

         "Type of traffic.";

       }

container cc-ipv4-sessions-statistics {

        when "../type = 'ipv4'" {

         description

          "Only applies when traffic type is Ipv4.";

        }



      description

        "CC ipv4 sessions";

      uses cc-session-statistics;

    }

container cc-ipv6-sessions-statistics {

        when "../type = 'ipv6'" {

         description

          "Only applies when traffic type is Ipv6.";

        }

      description

        "CC ipv6 sessions";

      uses cc-session-statistics;

    }

                      description

      "List of CC session statistics data.";

                    }

                     description

    "CC operational information.";

  }

”



b) On p.9: " +--:(system-id)

      |                 +--rw system-id-location?      router-id"



Why isn't this just named router-id instead of system-id, for consistency?

This comment applies throughout the draft.



[Qin]: Okay, will fix this consistency issue.



c) The use of "tp" to mean test-point is a bit unfortunate in a model that is

building off of the network topology one, which uses "tp" for termination-point.



[Qin]: YANG validation tool doesn’t complain about this.



d) On p. 13: "identity address-attribute-types {

    description

      "This is base identity of address

       attribute types which are ip-prefix,

       bgp, tunnel, pwe3, vpls, etc.";

  }"



I haven't a clue what is meant by a bgp address attribute type or a tunnel one.

 Can you please expand the description to be substantially more meaningful?

How is it used?



[Qin]: Good comments, we actually reference RFC4379 for these address attribute types. The proposed changes look like as follows:

“

  identity address-attribute-types {

    description

      "This is base identity of address

       attribute types which are Generic

IPv4/IPv6 Prefix,BGP Labeled

IPv4/IPv6 Prefix,Tunnel ID,

       PW ID, vpls VE ID, etc.(See RFC4379

                       for details.)";

  }

”

On p. 24, I see these defined

" case bgp {

            leaf bgp {

              type inet:ip-prefix;

              description

                "BGP Labeled Prefix ";

            }

          }

          case tunnel {



            leaf tunnel-interface {

              type uint32;

              description

                "VPN Prefix ";

            }

          }

          case pw {

            leaf remote-pe-address {

              type inet:ip-address;

              description

                "Remote pe address.";

            }

"

but unlike the other cases with clear descriptions and references to the

relevant RFCs, these are NOT clear and do not even fully expand acronyms.



[Qin]: Same as above, we will add RFC4379 as reference. Thanks.



e) "grouping tp-address-ni "  Please expand what NI is the abbreviation for in

the description.



[Qin]: Okay. Thanks.