Cryptographic Protocols

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Presentation transcript:

Cryptographic Protocols ■ Entity Authentication ■ Key Agreement ■ Fiat-Shamir Identification Schemes ■ Zero-Knowledge Proof Systems ■ Shnorr’s Identification/Signature Scheme ■ Commitment Schemes ■ Secret Sharing ■ Electronic Election

Entity Authentication Problem: Alice wants to prove to Bob that she is Alice and/or vice versa. Private-key based schemes Public-key based schemes Integrated with key agreement Zero-knowledge identification schemes

Key Agreement/Distribution

Identification Schemes based on zero-knowledge interactive proof systems

Zero-Knowledge Proof Systems

Shnorr’s Identification Scheme Another example of zero-knowledge interactive proof system Involving proof of knowledge of discrete logarithm

Commitment Schemes

Secret Sharing

Electronic Vote

Blind Signature