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Chapter 11: Message Authentication and Hash Functions

May 01, 2013

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2. Message Authentication. message authentication is concerned with: protecting the integrity of a message validating identity of originator non-repudiation of origin (dispute resolution) three alternative functions used:message encryptionmessage authentication code (MAC)hash function. 3. Broader Set of Attacks.

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Chapter 11: Message Authentication and Hash Functions

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Chapter 12: Hash and MAC Algorithms

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Chapter 12: Hash and MAC Algorithms

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453 Network Security. Section 3b: Message Authentication and Public-Key Cryptography Dr. E.C. Kulasekere Sri Lanka Institute of Information Technology - 2006. Requirements for Hash Functions. can be applied to any sized message M, produces fixed-length output h

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Hash Functions

Hash Functions. Nathanael Paul Oct. 9, 2002. Hash Functions: Introduction. Cryptographic hash functions Input – any length Output – fixed length H(x) – easy H(x) – one way “hard to invert” H(x) collision free. Purposes for hash functions. Data Integrity Ex: Tripwire Message digest

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Hash and Mac Algorithms

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