IPPM / IETF 121 Dublin

Chairs: Tommy Pauly & Marcus Ihlar
Notetaker(s): Caspar Schutijser, Craig Taylor

Working Group Documents

Intro by chairs

draft-ietf-ippm-capacity-protocol (10 minutes)

Speaker: R. Geib

Q&A

Marcus Ihlar - Len Ciavattone has an implementation. Is he up to speed?
[did not get answer]

Ruediger Geib: co-author usually first implements before updating the
draft, but not sure.

Greg Mirsky - "This has been implemented by the open broadband
initiative"

Tommy made a procedural point about "last call"; It wasn't obvious
whether there was an action point: Perhaps he can review.

draft-ietf-ippm-hybrid-two-step and draft-ietf-ippm-asymmetrical-pkts (15 minutes)

Speaker: G. Mirsky

Q&A for draft-ietf-ippm-hybrid-two-step

Question from the chairs about readers and reviewers of the draft: About
5x readers in the room and 4 reviewers.

Q&A for draft-ietf-ippm-asymmetrical-pkts

Ruediger: Believes the names is misleading [packets] asymmetrical
packets vs asymmetrical traffic

Greg: leaning toward renaming from asymmetric packets to asymmetric
traffic, and is more than half way through the existing feedback.

draft-ietf-ippm-stamp-ext-hdr (10 minutes)

Speaker: R. Gandhi

Q&A

Giuseppe Fioccola: comment: add reference to document that I'm
presenting later about the idea to combine active tools and hybrid
methods for hop-by-hop measurements.

Rakesh: we can think about it.

Tommy: as an informative reference?

Giuseppe: yes.

draft-olden-ippm-qoo (10 minutes)

Speaker: B. Tiegen

Q&A

Stuart Cheshire: would be great if you can present this at the IEEE
meeting next week. There's fairly contentious discussion in Wi-Fi
community. IEEE don't want to add CC/reponsiveness data at the protocol
as it's a "layer violation", this helps to inform that conversation.

Tommy Pauly: how are the categories corresponding to particular
application services like WebEx, Zoom, etc.? Were the people
self-indicating what they were running?

Speaker: numbers are hyphotethical if you run a video conferencing tool.
...

Tommy: being able to distinguish between application-platform pairs
(e.g., FaceTime on iOS 18 vs WebEx on Linux) is useful.

Ruediger: the scale is not a moss scale and not reflecting user
experience, correct?

Speaker: correct.

Juan-Carlos Zuniga: correlating to MAC address: there's MAC address
randomization now so be aware of that. Second point: at IEEE next week
we're ineed discussing these topics. Third: they want to know exactly
what you are measuring. Objective.

Abhishek Tiwari: similar median results, more outliers for wifi. users
suffer more often from problems.

Speaker: goal about improving quality is to make the instances of bad
performance more rare

Tommy:

Speaker: a lot of the problems with wifi due to wifi congestion and due
to range

Jason Livingood: turning measurements into actionable recommendations is
what users need.

Gaetan F?: Are you measuring signal strengts and all of those?

Speaker: yes.

(Not sure who cntd.): have you compared router measurements to QoE
measurements provided by user applications/devices?

Speaker: yes, but only on small scale.

draft-ietf-ippm-responsiveness (20 minutes)

Speaker: S. Cheshire

Q&A

Greg Mirsky: interesting point whether this metric allows separation of
network measurement and application measurement. E.g., separate
propagation from queueing.

Speaker: we want to measure things that affect behavior for
applications. so no separation between network and application possible
per se, but we want to minimize impact of application.

Speaker: we want to make it hard to cheat on this benchmark.

Abhishek Tiwari: couple points. Repeatability requirement: some amount
of variance is expected on the Internet.

Speaker: agree. 0 variance is not realistic but a small percentage
variance is realistic. should be low enough so you trust the results of
the measurements.

Abhishek: second point: RPM measurements: surprised to see "throw away 5
% of worst measurements". Outliers are very important.

Speaker: personal view is throwing that away is not the right thing to
do but it does make measurements more repeatable. But it's a workgroup
consensus document.

Warren Kumari: output of tests depends on whether people on same network
(e.g. family member) are using the network heavily.

Speaker: widely held view that performance degrades if people are using
the network. But a video conference can be a 1 Mbit/sec data stream and
it should still work well if other people are using the network. The
Internet is a shared network but we have not learned how to share it
very well.

Warren: agree that's not how the network should be but it is.

Timothy Panton: I can help a bit on how video conferencers think. Two
basic algorithms: one is to estimate bandwidth and push down until you
get to what you can achieve end-to-end. Second: ask for retries until
you get full packet.

Speaker: have heard different perspectives on how video conferencers do
it. need input.

...: ...

Bjorn Teigen: support for not throwing away the worst 5 percent.

Jonathan Lennox: video is complicated and fairly loss-tolerant; audio
less so. Also rexample of glitches that happen that make a bad
experience. E.g. once a minute a Wi-Fi channel scan which turns itself
off for 500 milliseconds.

Speaker: audio probably a better example than video

draft-ietf-ippm-alt-mark-deployment (10 minutes)

Speaker: G. Fioccola

Q&A

Greg: propose to look at hybrid two-step. Would like to work with you.

Speaker: thinking of adding reference to your document during your
presentation. Lets' talk offline.

Proposed Work

draft-ydt-ippm-alt-mark-yang (10 minutes)

Speaker: G. Fioccola

Q&A

Greg: approproate to work on this. Would like to discuss later: mark
packet ... accurate measurement of delay but also generate operational
information analogous to what's done with ...

draft-fioccola-ippm-on-path-active-measurements (10 minutes)

Speaker: G. Fioccola

Q&A

Xiao Min: there's a reference to a 6man draft. We now have a new, merged
draft that's replaces the old one.

Speaker: thank you.

draft-zhang-ippm-stamp-mp (10 minutes)

Speaker: L. Zhang

Q&A

Greg Minsky: measurements are useful, but measurements can already be
realized [did I get that correctly?].

Speaker: it's hard to make sure everything is measured (e.g., using IP
header information to generate entropy)

Rakesh Gandhi: is it intentional that forwarding nodes have to parse big
part of packets? [did I get that right?]

Xiao Min: current devices do not have the capabilities that you require

Lightning Talks

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