Re: [tsvwg] Another tunnel/VPN scenario (was RE: Reasons for WGLC/RFC asap)

[Jonathan Morton <[e-mail]>]

> On 3 Dec, 2020, at 6:40 pm, Gorry Fairhurst <[e-mail]> wrote:
> 
>> Frankly, the sooner the WG understands and accepts that basic fact, the sooner we can move to a viable solution - one which does not redefine CE from the semantics established by RFC-3168 and RFC-8511, and hence does not place burdens on networks which have no interest in the L4S experiment.
> 
> I think we need to be clear that I understand the proposal is to an Internet-wide experimental deployment.

An Internet-wide experiment will inevitably need to deal with a lot of "legacy" networks which have never even heard of L4S, have no pressing desire to change their equipment to accommodate it, and might find it challenging (or at least costly) to do so even if they desired to.  This especially includes those networks which have already invested in deploying plain old ECN, most of whom will have done so relatively recently and are still depreciating those assets.

That's precisely why L4S needs to show that it is safe to deploy into legacy networks, which may depend on existing RFC-3168 assumptions for their operation, before it can be approved for an Internet-wide experimental deployment.  We have been trying to make that point for two years already, including through several of the issues (still open) raised at the previous L4S WGLC at Montreal.  Meanwhile, ECN deployment has been increasing (see Jake's data).

 - Jonathan Morton