Re: [quicwg/base-drafts] Make transport parameter ID and length varint (#3294)

Kazuho Oku <> Wed, 11 December 2019 04:36 UTC

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Date: Tue, 10 Dec 2019 20:36:32 -0800
From: Kazuho Oku <>
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Subject: Re: [quicwg/base-drafts] Make transport parameter ID and length varint (#3294)
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I also think that we do not need more than 2^16 space for Transport Parameters.

In addition to what we know from how TCP options are being used (as @janaiyengar points out), I would also point out that every TP consumes space in the handshake packets that the endpoints exchange. To paraphrase, there is an incentive to keep the number of TPs being used small. I do not think we'd ever see endpoints sending thousands of TPs.

Assuming that is the case, there is no practical reason to switch to varints. As I have pointed out in #3020, some of us have been reusing a encoder / decoder designed for TLS, switching to a varint-based design would require those to write a new codec specifically for QUIC. That's just a burden.

I think we should concentrate on fixing real issues rather than requiring everybody to make an unneeded change. 

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