Re: Preparing for discussion on what to do about the multipath extension milestone

[Olivier Bonaventure <[e-mail]>]

Spencer,
> 
> On Fri, Sep 25, 2020 at 5:00 AM Lars Eggert <[e-mail] 
> <mailto:[e-mail]>> wrote:
> 
>     In parallel to progressing the "base drafts" towards RFC
>     publications, the WG should now also begin to pick up the pace on
>     our other adopted work items (ops drafts, extensions, etc.)
> 
>     One important other discussion item is what to do about the
>     multipath extension milestone, which some have suggested should be
>     dropped, while others still show interest to pursue it.
> 
> 
> So, I'd like to understand the suggestion to drop this milestone, before 
> I start trying to discuss that suggestion :-).

I'd like to understand this as well.
> 
> In conversations with individual folk, I've heard these concerns about 
> QUIC multipath:
> 
> - Whether it will be possible to evaluate multipath performance at 
> scale, both for evaluating proposals and testing implementations.

We already have plenty of experience with MPTCP with several large 
deployments, including :

- MPTCP on all iPhones since 2013 with a growing number of applications
- MPTCP on Android smartphones in South Korea for WiFi/4G offload
- MPTCP in hybrid access networks that are used by different network 
operators to combine xDSL and LTE

Multipath extensions to QUIC would be applicable in these different use 
cases

> - The complexity involved in making decisions dynamically about which 
> path to send a given packet on (which could be a research topic, given 
> certain constraints and goals).

The packet scheduling problem is a much simpler problem in multipath 
transport protocol than congestion control. I would not consider this as 
a research topic given all the experience we have with MPTCP

> If I've misunderstood or misquoted, my apologies, of course. Please 
> correct me.
> 
> What other concerns do people have? I'd like to get all the objections 
> out at the beginning of the discussion.

Same for me


Olivier