This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: COMS W4995 Introduction to Cryptography October 30, 2003 Lecture 18: Digital Signature Schemes Lecturer: Tal Malkin Scribes: Hua Shuo Cai Summary Definition of Digital Signature scheme. Brief description of Paradox. And construc tion of Lamport’s OneTime Signature for one bit message. 1 Authenticity How do you know that relieved message is from who you think it is? And that it wasn’t tampered with? Adv can intercept the cipher and change the cipher. We have two authentication schemes : • DigitalSignature Public Key World. • MessageAuthenticationCode Private Key World. 2 Digital Signature Definition 1 A Digital Signature Scheme is a triple of algorithms { GEN, SIGN, V ER } such that: • GEN (The key generate algorithm)  a randomized algorithm that on input 1 k outputs ( P K, SK ) . • SIGN (The Signing algorithm) a (Possibly randomized algorithm) that on in put SK , m output a signature σ ....
View
Full
Document
This note was uploaded on 01/30/2008 for the course ICS 268 taught by Professor Jarecki during the Fall '04 term at UC Irvine.
 Fall '04
 Jarecki

Click to edit the document details