Subject: Interim meeting request for slides on multipath QUIC use cases and requirements

From: Lucas Pardue <[email-masked]>
Date: Tue, 13 Oct 2020 14:10:58 +0100

Hi folks,

In the upcoming interim related to multipath QUIC, the chairs would like to
allocate a small bit of agenda time to hear people's use cases. We'd like
to spend no more than 5 minutes per non-intersecting deployment use cases
(e.g. we'd hear about Apple's use of multipath in one presentation only,
ideally from Apple folks themselves). Presenters should also include
requirements or non-requirements in the context of what is currently not
supported in QUICv1.

We invite people to nominate a speaker that will submit slides in PDF
format as a Pull Request to the QUIC WG materials repository interim-20-10
folder [1]. We'll consider these as we update the agenda in the lead up to
the meeting.

Cheers,
Lars and Lucas
QUIC WG Chairs

[1] https://github.com/quicwg/wg-materials/tree/master/interim-20-10

---

From: Spencer Dawkins at IETF <[email-masked]>
Date: Tue, 13 Oct 2020 10:35:38 -0500

Dear Chairs,

I'd like to do one or two slides, five minutes max, on the multipath modes
that are under discussion in 3GPP SA2, from my perspective as an
individual.

If you get a better offer on that, please take it, but I think that's
important to include in decisions about what multipath QUIC should (and
should not) look like.

When do you need the slides?

Best,

Spencer

On Tue, Oct 13, 2020 at 8:11 AM Lucas Pardue <[email-masked]>
wrote:

> Hi folks,
>
> In the upcoming interim related to multipath QUIC, the chairs would like
> to allocate a small bit of agenda time to hear people's use cases. We'd
> like to spend no more than 5 minutes per non-intersecting deployment use
> cases (e.g. we'd hear about Apple's use of multipath in one presentation
> only, ideally from Apple folks themselves). Presenters should also include

---

From: Lars Eggert <[email-masked]>
Date: Wed, 14 Oct 2020 12:45:22 +0300

Hi,

On 2020-10-13, at 18:35, Spencer Dawkins at IETF <[email-masked]> wrote:
> I'd like to do one or two slides, five minutes max, on the multipath modes that are under discussion in 3GPP SA2, from my perspective as an individual.

I think that would be helpful, and so far there are no other offers to summarize those use case requirements.

> When do you need the slides?

Monday at the latest?

Thanks,
Lars

---

From: Gorry Fairhurst <[email-masked]>
Date: Wed, 14 Oct 2020 11:22:54 +0100

Maybe it's just me - but I would be super-interesting in checking that I 
really understand what the migration feature of QUIC would give us if 
there was a change in connectivity.

Am I correct, in seeing QUIC as already having (or nearly having) a path 
failover method - similar to SCTP failover? ... where multiple paths are 
kept alive, but only one path is used at a time for data. Can some 
problems be solved by a simple failover method?

To me multipath, is where performance optimisation questions are solved 
- such as how to have simultaneous use of capacity across multiple paths 
(some people call this bonding), or scheduling across paths to 
minimising the delay, or one of many other metrics.

Just a thought on what might be useful to me to see in some slides .... 
perhaps before we delive into the details of policies and scheduling.

Gorry

---

From: Martin Duke <[email-masked]>
Date: Wed, 14 Oct 2020 08:48:33 -0700

Gorry, that is my understanding as well. If we don't have failover, we've
messed up in some way.

On Wed, Oct 14, 2020 at 3:23 AM Gorry Fairhurst <[email-masked]>
wrote:

> >> I'd like to do one or two slides, five minutes max, on the multipath
> modes that are under discussion in 3GPP SA2, from my perspective as an
> individual.

---

From: Mikkel Fahnøe Jørgensen <[email-masked]>
Date: Wed, 14 Oct 2020 08:53:03 -0700

Failover only works for clients. For server p2p you do not have such a
fallback and servers often have a private and a public IP.

Kind Regards,
Mikkel Fahnøe Jørgensen

On 14 October 2020 at 17.49.05, Martin Duke ([email-masked]) wrote:

---

From: Cyrill Krähenbühl <[email-masked]>
Date: Thu, 15 Oct 2020 18:17:20 +0200

Dear Chairs,

I'm a researcher at ETH Zurich working in the field of multipath, in 
particular in the context of the future Internet architecture SCION, and 
path-aware networks (IRTF PANRG).

We are researching inter-domain multipath offered by the network 
infrastructure, which is different from multi-interface or multi-homing 
based multipath as assumed by MPTCP. In a SCION-based setting, we 
observe a large number of distinct paths that can be used, typically 
around 10, but for larger distances we observe even 50-100 different paths.

In this context, we see two topics of potential interest. First, 
multipath scheduling, which has a large impact on the performance of a 
multipath transport protocol, becomes challenging since we might not be 
able to continuously probe 10+ (or even 100+) paths to infer which paths 
to send traffic on.

Second, the SCION architecture can offer additional information for 
paths, for instance AS-level information, lower bound on end-to-end path 
latency, expected bandwidth, etc. An interesting challenge is how to 
expose this path information to applications or transport protocols, so 
that path optimization is possible for instance for different QUIC streams.

The extensibility of (MP)QUIC provides an interesting platform to allow 
endpoints to use additional path information in the scheduling 
algorithm, negotiate paths with desirable properties between endpoints, 
and map QUIC data streams to specific paths.

If the working group is interested and this use case has not already 
been discussed in the group, I would be happy to give a short 
introduction in the interim meeting.

Best,
  Cyrill Krähenbühl

Best,
  Cyrill

On 13.10.20 15:10, Lucas Pardue wrote:
> Hi folks,
>
> In the upcoming interim related to multipath QUIC, the chairs would 
> like to allocate a small bit of agenda time to hear people's use 
> cases. We'd like to spend no more than 5 minutes per non-intersecting 
> deployment use cases (e.g. we'd hear about Apple's use of multipath in 
> one presentation only, ideally from Apple folks themselves). 
> Presenters should also include requirements or non-requirements in the 
> context of what is currently not supported in QUICv1.
>
> format as a Pull Request to the QUIC WG materials repository 
> interim-20-10 folder [1]. We'll consider these as we update the agenda 
> in the lead up to the meeting.
>
> Cheers,
> Lars and Lucas
> QUIC WG Chairs
>
>

---

From: Lars Eggert <[email-masked]>
Date: Thu, 15 Oct 2020 19:36:47 +0300

Hi,

On 2020-10-15, at 19:17, Cyrill Krähenbühl <[email-masked]> wrote:
> In this context, we see two topics of potential interest. First, multipath scheduling, which has a large impact on the performance of a multipath transport protocol, becomes challenging since we might not be able to continuously probe 10+ (or even 100+) paths to infer which paths to send traffic on.
> 
> Second, the SCION architecture can offer additional information for paths, for instance AS-level information, lower bound on end-to-end path latency, expected bandwidth, etc. An interesting challenge is how to expose this path information to applications or transport protocols, so that path optimization is possible for instance for different QUIC streams.
...
> If the working group is interested and this use case has not already been discussed in the group, I would be happy to give a short introduction in the interim meeting.

thanks for the offer!

There are all kinds of interesting research questions related to multipath in general and for QUIC in particular, including the ones you outline above.

The reason we're scheduling the interim is to help us decide if the QUIC working group should start any standards activity in the multipath space, and more concretely, what the desired (= currently missing) functionality is that will need standardization. A key focus of interest are the large deployments of IETF QUIC that are currently being planned or are already underway. I'm not sure to what degree a presentation on research challenges would inform that decision?

Thanks,
Lars

---

From: Cyrill Krähenbühl <[email-masked]>
Date: Thu, 15 Oct 2020 19:45:05 +0200

Hi Lars,

While this use case is not about a very large deployment such as Apple's 
MPTCP, some of the discussion points in the email thread about the 
multipath extension milestone (e.g., mapping flows to paths, exchanging 
control information relevant for multipath between endpoint, policies 
for scheduling in MPQUIC) resonated with what we are working on.
I thought it might be interesting to present a use case in a different 
area (future Internet architecture) that requires similar 
functionalities from a multipath transport layer protocol.

In any case, if the working group decides to start standardization 
efforts in this direction, I would be happy to discuss useful 
functionalities for future Internet architectures at another meeting.

Best,
  Cyrill

---

From: "Qing An" <[email-masked]>
Date: Fri, 16 Oct 2020 15:33:08 +0800

Dear Chairs,

Alibaba is highly interested in multipath QUIC so we would like to share some of use cases we think are important from Alibaba's point of view.  A five-minute presentation slot should be good enough.

Our presentation will focus on the following use cases:
1. New-retail e-commerce, which includes but is not limited to short-form video, video/file uploading and live online shopping.  A multipath quic demo in Taobao will presented.
2. Extreme mobility use cases, especially for customers who want to get access to online shopping on high-speed rails. 
3. 5G related use cases. We would like to discuss some of the challenges we have observed on the sub-6GHZ NSA 5G networks which could be potentially addressed with multipath QUIC technology.

The slides will be provided before next Wednesday.

Best,

Qing An
Alibaba

------------------------------------------------------------------
From:Lucas Pardue <[email-masked]>
Send Time:2020年10月13日(星期二) 21:11
To:QUIC WG <[email-masked]>
Cc:Lars Eggert <[email-masked]>
Subject:Interim meeting request for slides on multipath QUIC use cases and requirements

Hi folks,

In the upcoming interim related to multipath QUIC, the chairs would like to allocate a small bit of agenda time to hear people's use cases. We'd like to spend no more than 5 minutes per non-intersecting deployment use cases (e.g. we'd hear about Apple's use of multipath in one presentation only, ideally from Apple folks themselves). Presenters should also include requirements or non-requirements in the context of what is currently not supported in QUICv1.

We invite people to nominate a speaker that will submit slides in PDF format as a Pull Request to the QUIC WG materials repository interim-20-10 folder [1]. We'll consider these as we update the agenda in the lead up to the meeting.

Cheers,
Lars and Lucas
QUIC WG Chairs

---

From: Lars Eggert <[email-masked]>
Date: Fri, 16 Oct 2020 10:44:21 +0300

Hi Qing,

> Alibaba is highly interested in multipath QUIC so we would like to share some of use cases we think are important from Alibaba's point of view.  A five-minute presentation slot should be good enoug…

thank you for the offer - it would be very interesting to see your use cases presented, and what features you are missing in QUICv1 to support them.

That said, I think you are extremely optimistic when you say that you can cover all of the topics below in five minutes. Could I ask that you focus on those one or two use cases - and their requirements - that you see the most immediate need for?

> The slides will be provided before next Wednesday.

If at all possible, we'd like the slides closer to the beginning of the week. This goes for all presentations; Lucas and I intend to go through the slides beforehand to give feedback to the presenters, e.g., in case there is significant overlap between slide decks.

Thanks,
Lars

---

From: "Qing An" <[email-masked]>
Date: Fri, 16 Oct 2020 19:41:46 +0800

Hi Lars,

> If at all possible, we'd like the slides closer to the beginning of the week. This goes for all presentations; Lucas and I intend to go through the slides beforehand to give feedback to the present…

We will try to provide the slides on next Monday. Maybe we can discuss the priority of the use cases after you go through the slides.

Thanks,
Qing

---

From: Lars Eggert <[email-masked]>
Date: Fri, 16 Oct 2020 14:46:03 +0300

Hi,

> We will try to provide the slides on next Monday. Maybe we can discuss the priority of the use cases after you go through the slides.

thanks! We can discuss the priority, but we are actually mostly interested what *your* priority is.

Thanks,
Lars

---

From: "Qing An" <[email-masked]>
Date: Fri, 16 Oct 2020 20:11:42 +0800

Hi,

> thanks! We can discuss the priority, but we are actually mostly interested what *your* priority is.

Actually, the order of the numbered use cases stands for our priority.

Thanks,
Qing

---

From: Spencer Dawkins at IETF <[email-masked]>
Date: Fri, 16 Oct 2020 07:44:33 -0500

Dear QUIC chairs,

> important to include in decisions about what multipath QUIC should (and

I've created https://github.com/quicwg/wg-materials/pull/157 with my
slides. I'm happy to take feedback about them, from anyone.

Just to clarify for everyone who's trying to figure out what will be
discussed at the interim meeting, my focus is on ATSSS steering modes. I
know other people are talking about specific use cases, and look forward to
understanding those, too!

Best,

Spencer

> Spencerls/tree/master/interim-20-10
> <https://github.com/quicwg/wg-materials/tree/master/interim-20-10>
>

---

From: Christoph Paasch <[email-masked]>
Date: Fri, 16 Oct 2020 10:44:20 -0700

Dear chairs,

I would like to present Apple's usecases for Multipath transport. Notably,
the use of multipath for Siri and Apple Music (cfr., my previous email).

I will prepare the slides and send a pull-request beginning of next week.

Thanks,
Christoph

---

From: Olivier Bonaventure <[email-masked]>
Date: Mon, 19 Oct 2020 09:40:43 +0200

Dear Lars and Lucas,
> only, ideally from Apple folks themselves). Presenters should also 
> include requirements or non-requirements in the context of what is 
> currently not supported in QUICv1.
> 

I've created a pull request with some slides describing the hybrid 
access networks use case and the requirements on MPQUIC

Best regards,

Olivier

---

From: Mikkel Fahnøe Jørgensen <[email-masked]>
Date: Mon, 19 Oct 2020 00:47:59 -0700

I could also see a hybrid use case where video is buffered using a low cost
high latency link, while the immediate next frames are served on a high
priority link of possibly limited bandwidth.

Kind Regards,
Mikkel Fahnøe Jørgensen

On 19 October 2020 at 09.41.05, Olivier Bonaventure (
[email-masked]) wrote:

Dear Lars and Lucas,

Best regards,

Olivier

---

From: "Qing An" <[email-masked]>
Date: Mon, 19 Oct 2020 22:49:54 +0800

Dear Chairs,

I just made a pull request to add MPQUIC use cases from Alibaba.

https://github.com/quicwg/wg-materials/pull/159

BR,
Qing
Alibaba

Dear Chairs,

Best,

Qing An
Alibaba

Hi folks,

Cheers,
Lars and Lucas
QUIC WG Chairs