Subject: Passwords again

From: [email-masked]
Date: Thu, 14 Oct 1993 08:15:27 -0700

How about something like a zero-knowledge proof?  (This is a proof in which
you prove that you know something, without revealing what it is that you
know.)

Or some sort of symmetric handshake using a public-key system?

Unfortunately, both of these are rather computationally expensive.
Surely there's a better way, that's secure enough for your purposes.