Definitions Data-Origin authentication message authentication Data Integrity Entity Authentication 復大辱软件学院 LiST
LiJT 6 Definitions • Data-Origin Authentication – message authentication • Data Integrity • Entity Authentication
Definitions Data-Origin Authentication Data Integ Early textbooks, viewed these two notions with no essential difference However, two very different notions Auth necessarily involves communications involves identifying the source of a message the most significantly, freshness of a message liveness of the message source message is fresh or not should be determined by apps 復大辱软件学院 LiST
LiJT 7 Definitions • Data-Origin Authentication • Data Integrity – Early textbooks, viewed these two notions with no essential difference – However, two very different notions • Auth. necessarily involves communications • involves identifying the source of a message • the most significantly, freshness of a message; liveness of the message source. – message is fresh or not should be determined by apps
Definitions Data Integrity Entity Authentication Often, a claimed identity in a protocol is a message in its own right. So, confidence about a claimed identity and about the liveness of the claimant can be established by applying data-origin authentication mechanisms 8 復大辱软件学院 LiST
LiJT 8 Definitions • Data Integrity • Entity Authentication – Often, a claimed identity in a protocol is a message in its own right. So, confidence about a claimed identity and about the liveness of the claimant can be established by applying data-origin authentication mechanisms
Authentication scheme · Weak authentication Passwords. pin. etc One-time passwords(semi-strong authentication) Strong(cryptographic)authentication Challenge- Response Mechanisms Zero-knowledge authentication Allow Claimant to demonstrate knowledge of a secret without revealing any information whatsoever of the secret 復大辱软件学院 LiST
LiJT 9 Authentication scheme • Weak authentication – Passwords, PIN, etc – One-time passwords(semi-strong authentication) • Strong (cryptographic) authentication – Challenge – Response Mechanisms • Zero-knowledge authentication – Allow Claimant to demonstrate knowledge of a secret without revealing any information whatsoever of the secret
Outline of talk Definitions Passwords Unix Passwords One time passwords Challenge-response techniques Basic protocol constructions Alsoone-time Authentication Involving TTP 復大辱软件学院 LiST
LiJT 10 Outline of Talk • Definitions • Passwords – Unix Passwords – One time passwords • Challenge-response techniques – Basic protocol constructions – Also “one-time” • Authentication Involving TTP