Re: [CFRG] RSA blind signatures

Michele OrrĂ¹ <lists@tumbolandia.net> Wed, 24 February 2021 08:17 UTC

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From: =?UTF-8?Q?Michele_Orr=C3=B9?= <lists@tumbolandia.net>
Date: Wed, 24 Feb 2021 09:17:24 +0100
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To: Christopher Wood <caw@heapingbits.net>
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Subject: Re: [CFRG] RSA blind signatures
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For those cases needing Privacy Pass but with public verifiability, I would
kindly ask CFRG to also take a second to evaluate blind BLS signatures.

It is true that verification would be much slower than RSA;  however, they
have efficient batching algorithms (for which the amortized cost is ~2
scalar multiplications) and the issuance protocol is literally the same as
a Privacy Pass.
Additionally, they have the same number of rounds and same number of
messages.

This would avoid perhaps creating an entire new standard and having just a
new section on the privacy pass draft?
Hoping to help,
--
Michele.