Re: [quicwg/base-drafts] Unclear what to do when QUIC Version Hints are missing (#3061)

Peter Wu <notifications@github.com> Tue, 24 September 2019 00:23 UTC

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Date: Mon, 23 Sep 2019 17:23:46 -0700
From: Peter Wu <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Unclear what to do when QUIC Version Hints are missing (#3061)
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The Version Hints presumably exist to avoid one roundtrip for the [Version Negotiation packet](https://tools.ietf.org/html/draft-ietf-quic-transport-23#section-17.2.1). Thus without hints, a client could probably decide to use any version it supports (1 or whatever latest version it desires to use).

FWIW Google uses alt-svc, but I do not remember seeing the version hint *parameters*. For example:
```
$ curl -sI https://google.com | grep alt-svc
alt-svc: quic=":443"; ma=2592000; v="46,43,39"
```

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