Quick Index

• Authentication Protocols and Some Flaws .
• Plan for Today .
• Goals for Today .
• Plan for Section on Authentication and Formal Methods .
• Starters .
• Notation .
• Needham -Schroeder [1978] .
• Flaw #1: Denning - Sacco Replay Attack .
• Denning - Sacco Fix [1981]: Use Timestamps .
• Needham -Schroeder Fix [1987]: Use Nonces .
• Other Flaws in Needham -Schroeder Protocols .
• Otway -Rees [1987] .
• Flaw # 1: Type Flaw .
• Flaw #2: M needs to be an unpredictable nonce. .
• Wide-Mouthed Frog [Burrows] .
• Flaws/Weaknesses .
• Flaw #2 .

Heather L. Marko

Modified: December 1997