Telechat Review of draft-ietf-tsvwg-ecn-experimentation-06

Request Review of draft-ietf-tsvwg-ecn-experimentation
Requested rev. no specific revision (document currently at 08)
Type Telechat Review
Team Ops Directorate (opsdir)
Deadline 2017-09-26
Requested 2017-09-04
Authors David Black
Draft last updated 2017-09-27
Completed reviews Genart Telechat review of -05 by Brian Carpenter (diff)
Secdir Telechat review of -05 by Hilarie Orman (diff)
Genart Telechat review of -06 by Brian Carpenter (diff)
Opsdir Telechat review of -06 by Susan Hares (diff)
Assignment Reviewer Susan Hares
State Completed
Review review-ietf-tsvwg-ecn-experimentation-06-opsdir-telechat-hares-2017-09-27
Reviewed rev. 06 (document currently at 08)
Review result Has Issues
Review completed: 2017-09-27


This is an OPS-DIR Review which focus the work on issues in deployed technology based on this RFC. 

Summary: Has issues as guide to experimental RFC .  To me these operational issues 
General comment: Thank you david for addressing this Area.  Better ECN control is critical to many portions of the network. 
                                   My comments on this draft are because I really hope you can do quality experiments. 

How this might be resolved: if there is a operational guidelines section (or separate document), that covered: 
a) how to set-up and determine if a ECT(1) experiment success or fails
b) how to manage your ECT(1) experiment in your network. 
c) how to manage and detect if your ECT experiment is running into problems with other IETF technology (TRILL, MPLS VPNs, IPVPNs, BIER and NV03 technology). 
d) Recommending a monitoring structure (e.g. yang modules, netconf/restconf and monitoring tools0 

Major issues: 

#1 There is nothing in this document which provide guidelines to the authors of experimental RFCs based in this draft on specific ways to 
    monitor the ECN experiments, report the ECN experimental data, or disable the experimental data.   If the success or failure of 
    an experiment is based on "popular vote" determined by deployment, then say state this point.  I personally would object to that 
   because you cannot tell if a limited experiment in a specific location (E.g. a data center) might be successful in another location. 

  If the success or failure of an experimental RFC is based on a specific set of criteria for ECN, then it would be good to give 
  an operational suggestion on how to: a) design an experiment, b) run an experiment and collect data, and c) report ths 
 data in order to standardize the ECN experiments using ECT(1). 

 page 10 section 4.2 last 2 paragraphs in sentence, hinted that you have an experiment in mind without specifying the experiment's 
 success or failure criteria other than popular vote.  Is this true?  if it is, this is problematic.  If I misunderstood your text, then please 
have someone re-read the text. 

I have read lots of papers on ECN. 

2) No discussion was given on how the TCP layer experimentation would impact routing layer handdlng of ECN. 
For example, the trill WG has the draft draft-ietf-trill-ecn-support.  Automated tunnel set-up for MPLS VPNS or IP VPNS may look at the ECN ECT(0)  or ECT(1).  TRILL's ECN supports the layer-2 within the data centers.  Some IP VPNS or MPLS VPNS may be needed for the data-center to business site 
 or data-center backup traffic.   
 As written, this draft allows loosening of the RFC3168 draft but does not provide guidelines  for network interaction.   

3)  Some networks also use the diff-service markings to guide traffic in the network. 
    This document does not suggest an operational check list on how to design an experiment that supports or does not support these markings. 

4) Modern operational IETF protocols and data modules for automating the tracking of these experiments should be suggests 

Some reviews have hinted that the text is repeats several sets of language.   People have found this lacked clarity.  One wonders why 
the authors did not simply provide a set of bis documents for RFC3168, RFC6679, RFC 4341, RFC4342, and RFC5622 if it is just updating 
the language in the specifications.  

This document tries to be both revision of the specifications and the architectural guidelines for experiments.  The dual nature does not lead 
to clarity on either subject. 

I did not do editorial nits due to the higher level issues.