Consensus Actions in Cipherspace?

[dmolnar]

On Fri, 12 Jan 2001, Ray Dillinger wrote:

> 
> 
> Are there any good general cryptographic protocols for groups 
> taking group actions by formal consensus or voting rules?

There are distributed signing protocols which could go partway towards
meeting this goal. For some details, you can look at the IBM project on
"Proactive Security" 
	http://www.hrl.il.ibm.com/Proactive/ 

They've implemented some of the protocols involved; there's a paper in ACM
CCS 5 I think which gives the API for their "Proactive Security Toolkit."
Java 1.1 implementation of distributed DSA signatures. Unfortunately, the
web page, which advertises a download for 8/99, seems to be out of date. 

	http://www.hrl.il.ibm.com/Proactive/project.html 

Now, if you could get your hands on this, then you could do what you want
by having each voter hold a share of the distributed secret key. The
voters agree amongst themselves however on what orders to sign, and then
execute distributed key signing to sign an order. The robot doesn't do
anything unless it receives a valid signed order. 

-David