Re: [TLS] TLS client puzzles

Brian Smith <> Wed, 29 June 2016 19:25 UTC

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From: Brian Smith <>
Date: Wed, 29 Jun 2016 09:25:44 -1000
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To: Dmitry Khovratovich <>
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Subject: Re: [TLS] TLS client puzzles
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Dmitry Khovratovich <> wrote:
> It allows cheap and memoryless verification by the server even though the
> puzzle solving guaranteely requires dozens of MB of RAM from a client

I feel like this is impractical simply because lots of people are
building HTTPS clients that don't even have dozens of MB of RAM total.
I think we should avoid doing anything that requires the client to
have more than ~16KB of memory total to devote to TLS stuff.
Otherwise, we force the internet to have an architecture where all
small devices require a smart proxy to solve these puzzles for them
and do other things.