Re: [quicwg/base-drafts] introduce a version alias mechanism (#2573)

Kazuho Oku <> Fri, 12 April 2019 02:41 UTC

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Date: Fri, 12 Apr 2019 02:41:02 +0000
From: Kazuho Oku <>
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Subject: Re: [quicwg/base-drafts] introduce a version alias mechanism (#2573)
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Asking mostly out of curiosity: do we need to scramble (or protect) other fields of a long header packet as well?

The (original) argument for having a version alias is to protect against accidental ossification of the protocol. That could happen on the other fields of v1 packet as well; namely the non-invariant fields of the first octet and the CIDL fields. If we scramble CIDL fields, it would not matter if the rest of the fields (e.g., token length) were kept as-is, assuming that the CID lengths have enough randomness to randomize the position of such fields.

Though the downside would be that servers would no longer be able to use the token to decipher the actual value of version number field.

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