Contract Enforcement in Cyberspace Public key encryption:Questions? We agree on a contract and an arbitrator Both of us digitally sign the contract And it includes the public key of the arbitrator I break the contract,you appeal to the arbitrator,he rules against me He writes up his decision,signs it using his private key Anyone can prove,by checking the signatures That the arbitrator I agreed on in advance ruled against me Thus reducing the information cost to third parties to near zero Contract Enforcement in Cyberspace • Public key encryption: Questions? • We agree on a contract and an arbitrator • Both of us digitally sign the contract • And it includes the public key of the arbitrator • I break the contract, you appeal to the arbitrator, he rules against me • He writes up his decision, signs it using his private key • Anyone can prove, by checking the signatures • That the arbitrator I agreed on in advance ruled against me • Thus reducing the information cost to third parties to near zero