Last Call Review of draft-ietf-alto-protocol-25
review-ietf-alto-protocol-25-opsdir-lc-schoenwaelder-2014-02-06-00

Hi,

I have reviewed draft-ietf-alto-protocol-25 for the OPS directorate
(OPS-DIR). The OPS-DIR reviews are focused on the operational and
manageability aspects of the documents using RFC 5706 as guidance.
Please consider these comments together with the other IETF Last Call
comments.

I enjoyed reading a very clear and well written document. As usual, I
appreciate the "Manageability Considerations" section, which provides
useful guidance.

For the monitoring part (16.1.4.), the document refers to
[I-D.ietf-alto-deployments]. While this I-D provides more discussion,
it still leaves it somewhat open how to effectively monitor the impact
ALTO has on the traffic. It seems difficult to me, within an ISP
network, to separate flows that are influences by an ALTO server from
other flows. The assumption that ALTO-enabled applications provide
that information back to an ISP running ALTO servers sounds a bit
idealistic to me. I also believe it is useful to distinguish
'measurement' from 'monitoring'. One likes to measure the impact an
ALTO server has on the traffic mix and one monitors the ALTO servers
whether they provides say function properly and achieve acceptable
response times.

Section 16.2.3. says "Monitoring ALTO Servers and Clients is described
in [I-D.ietf-alto-deployments]". Appendix A of this I-D talks about
monitoring (actually measuring) the effects of ALTO, but it does not
really talk about monitoring of ALTO servers or clients (e.g., is my
ALTO server getting overloaded?). Yes, some of this overlaps with
16.2.5 - perhaps provide a pointer.

Overall, I once again like to thank the authors for a very well
written document.

Editorial nits:

- p12: s/a defined groupings/defined groupings/

- p24: s/InforResourceDirectory/InfoResourceDirectory/

- p27: s/a the Retry-After/the Retry-After/

- p81: s/from a ALTO/from ALTO/

- p81: "The following is a list of suggested ALTO-specific to be
  monitored [...]" Missing noun?

- p86: s/are the rule/are the rules/

/js

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: +49 421 200 3587         Campus Ring 1, 28759 Bremen, Germany
Fax:   +49 421 200 3103         <

http://www.jacobs-university.de/

>