Identity-Based Encryption (IBE) is a cryptographic primitive that eliminates public key certificates by deriving user keys directly from arbitrary identities using bilinear pairings on elliptic curves, formalized through the security definition IND-CPA against adversaries with selective or adaptive identity exposure capabilities. The core mechanism relies on pairing-based cryptography to solve the Bilinear Diffie-Hellman problem, enabling a trusted authority to generate secret decryption keys corresponding to specific identities while maintaining indistinguishability of encrypted messages under chosen plaintext attacks in the random oracle model. This concept represents an abstraction within asymmetric encryption that simplifies key management but introduces distinct trade-offs regarding master secret compromise and revocation compared to traditional Public Key Infrastructure (PKI).
Identity-Based Encryption (IBE) is a cryptographic primitive that eliminates public key certificates by deriving user keys directly from arbitrary identities using bilinear pairings on elliptic curve…