Subject: [netconf] Tsvart last call review of draft-ietf-netconf-netconf-event-notifications-17

From: Wesley Eddy via Datatracker <[email-masked]>
Date: Tue, 02 Apr 2019 09:32:05 -0700

Reviewer: Wesley Eddy
Review result: Ready with Issues

This document has been reviewed as part of the transport area review team's
ongoing effort to review key IETF documents. These comments were written
primarily for the transport area directors, but are copied to the document's
authors and WG to allow them to address any issues raised and also to the IETF
discussion list for information.

When done at the time of IETF Last Call, the authors should consider this
review as part of the last-call comments they receive. Please always CC
[email-masked] if you reply to or forward this review.

I reviewed this in conjunction with the set of related WG documents on
NETCONF/RESTCONF subscriptions and event notifications.  I also have some
comments on other documents in the set, some of which may influence this once,
since they are closely related.

In figure 3, and text on page 11, there is an example with a DiffServ codepoint
value of "10".  This could be interpreted as binary, decimal, hexadecimal, etc.
 It should be clear what the base is supposed to be.  It seemed pretty
ambiguous in this and the related documents, so it's not apparent that an
implementer would be sure to get it right or for it to be compatible.

I have other broad comments on the DSCP usage that will be in review comments
for the subscribed-notifications draft where it is more appropriate.

---

From: "Eric Voit (evoit)" <[email-masked]>
Date: Wed, 10 Apr 2019 13:30:30 +0000

> From: Wesley Eddy, April 2, 2019 12:32 PM
> 
> Reviewer: Wesley Eddy
> review as part of the last-call comments they receive. Please always CC tsv-
> [email-masked] if you reply to or forward this review.
> 
> comments on other documents in the set, some of which may influence this
> once, since they are closely related.
> 

Hi Wesley,

Figure 3 includes the XML definition <dscp>10</dscp>
This is below the XML namespace "urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications"
 
In the "ietf-subscribed-notifications" YANG model where this "dscp" tag is defined, it is shown to be of:
      type inet:dscp;

higher in that YANG model, "inet" points to RFC 6991: Common YANG Data Types.  This is a core document for YANG which any YANG implementer should be familiar.

Within RFC 6991, the definition of "dscp" is

     typedef dscp {
       type uint8 {
         range "0..63";
       }
       description
        "The dscp type represents a Differentiated Services Code Point
         that may be used for marking packets in a traffic stream.
         In the value set and its semantics, this type is equivalent
         to the Dscp textual convention of the SMIv2.";
       reference
        "RFC 3289: Management Information Base for the Differentiated
                   Services Architecture
         RFC 2474: Definition of the Differentiated Services Field
                   (DS Field) in the IPv4 and IPv6 Headers
         RFC 2780: IANA Allocation Guidelines For Values In
                   the Internet Protocol and Related Headers";
     }

Hopefully this will address the ambiguity.  

Thanks,
Eric

> I have other broad comments on the DSCP usage that will be in review
> comments for the subscribed-notifications draft where it is more appropriate.