Re: Server Push, Alt-Svc and connection switching

Daniel Stenberg <daniel@haxx.se> Thu, 17 October 2019 17:47 UTC

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Date: Thu, 17 Oct 2019 19:44:26 +0200 (CEST)
From: Daniel Stenberg <daniel@haxx.se>
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To: Ryan Hamilton <rch@google.com>
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Subject: Re: Server Push, Alt-Svc and connection switching
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On Thu, 17 Oct 2019, Ryan Hamilton wrote:

> I think that the browser *should* be able to use the pushed resources 
> regardless of the connection that was used to push them. In your example, 
> even though the receipt of the alt-svc header might result in the creation 
> of an h3 connection, the browser *should* still be able to find the h2 
> pushes.

If the client uses a "push cache", I think it makes sense for that cache to 
work across HTTP/2 and HTTP/3 since otherwise the upgrade itself risk wasting 
resources that were already pushed to the client. It would also otherwise risk 
the same thing if the client deems it needs to fallback to h2 after having 
received pushed resources over h3...

-- 

  / daniel.haxx.se