Re: [Lime] Last Call: <draft-ietf-lime-yang-connectionless-oam-11.txt> (Generic YANG Data Model for Connectionless Operations, Administration, and Maintenance(OAM) protocols) to Proposed Standard

[Qin Wu <[e-mail]>]

-----邮件原件-----
发件人: Brian E Carpenter [mailto:[e-mail]] 
发送时间: 2017年10月21日 3:29
收件人: Greg Mirsky; [e-mail]; [e-mail]
抄送: Carlos Pignataro; [e-mail]; [e-mail]
主题: Re: [Lime] Last Call: <draft-ietf-lime-yang-connectionless-oam-11.txt> (Generic YANG Data Model for Connectionless Operations, Administration, and Maintenance(OAM) protocols) to Proposed Standard

Greg,
On 21/10/2017 01:34, Greg Mirsky wrote:
...
> 
>       session-delay-statistics and session-jitter-statistics are too 
> limiting in many dimensions - no support to reflect one-way (far-end 
> and near-end) and round-trip measurements for the same test session, 
> and too few metrics., e.g. no report of percentile.
> 
>       -
> 
>       session-delay-statistics does not reflect type of delay 
> variation being calculated. As analyzed in RFC 5481, PDV and IPDV 
> characterize different conditions (Section 5) and at least reflecting 
> which one being calculated and reported is very informative.
> 

I had similar comments on draft-ietf-lime-yang-connectionless-oam-methods-09
in my Gen-ART review at
https://mailarchive.ietf.org/arch/msg/gen-art/qA38WYm5ookOePfnhqO4yM09cvc.
I haven't reviewed draft-ietf-lime-yang-connectionless-oam itself, but it seems that the authors have chosen to leave quite a few things under-defined, which bothers me from the interoperability viewpoint.
Presumably the existing implementations have taken specific decisions on these points, which could be documented, even as default recommendations?

[Qin]: Thanks Brian for Good suggestion, here is proposed change to address your comments:
OLD TEXT:
"
  grouping session-delay-statistics {
    description
      "Grouping for per session delay statistics";

    container session-delay-statistics {
      description
        "Session delay summarised information.";
 ........

  grouping session-jitter-statistics {
    description
      "Grouping for per session jitter statistics";
    container session-jitter-statistics {
      description
        "Session jitter summarised information.";
.......
"
NEW TEXT:
"
  grouping session-delay-statistics {
    description
      "Grouping for per session delay statistics";
    container session-delay-statistics {
      description

        "Session delay summarised information.By default,
         one way measurement protocol (e.g., OWAMP)is used
         to measure delay. When two way measurement protocol
         (e.g., TWAMP) is used instead, it can be indicated
         using and protocol-id defined in RPC operation of
         draft-ietf-lime-yang-connectionless-oam-methods,i.e.,
         set protocol-id as OWAMP. Note that only one measurement
         protocol for delay is specified every time for interoperability reason.";
......

  grouping session-jitter-statistics {
    description
      "Grouping for per session jitter statistics";
    container session-jitter-statistics {
      description
        "Session jitter summarised information. By default,
         jitter is measured using IP Packet Delay Variation
         (IPDV) as defined in RFC3393. When the other measurement
         method is used instead(e.g.,Packet Delay Variation used in
         Y.1540, it can be indicated using protocol-id-meta-data
         defined in RPC operation of
         draft-ietf-lime-yang-connectionless-oam-methods. Note that
         only one measurement method for jitter is specified every time
         for interoperability reason.";
.....
"
Regards
     Brian