X-From-Line: nobody Sat Mar 13 00:11:27 1999 To: spki@c2.net Subject: An alternative way to do 1-of-N certificates? From: Paul Crowley Date: 13 Mar 1999 00:11:26 +0000 Message-ID: <876786jljl.fsf@hedonism.demon.co.uk> X-Mailer: Gnus v5.5/XEmacs 20.4 - "Emerald" Lines: 18 Xref: hedonism.demon.co.uk misc-mail:1321 X-Gnus-Article-Number: 1321 Sat Mar 13 00:11:27 1999 While I'm asking about some of the things in the SPKI draft, here's another possibility: I think there's an alternative secure way to do 1-of-N certificates that might be more convenient and flexible while still retaining security, though I'm not so sure it's as easy to reason about. To delegate a fraction of a priviledge, delegate the priviledge to a local name that you control, but don't directly certify that name as belonging to any key. Instead write people certificates entitling them to some fraction of that name, and use rational arithmetic in the verifier to make sure that all the fractions approving an action add up to one. This I think allows you to do all the arbitrarily subtle things that secret sharing schemes can do while keeping it to a fairly simple framework. Thoughts? -- __ \/ o\ paul@hedonism.demon.co.uk http://www.hedonism.demon.co.uk/paul/ \ / /\__/ Paul Crowley Upgrade your legacy NT machines to Linux /~\