About the Key Escrow Properties of Identity Based Encryption Schemes

IBE (Identity Based Encryption) represents a type of public key encryption that allows a party to encrypt a message using the recipient’s identity as public key. The private keys needed for decryption are generated and distributed to each party by a KGC (Key Generation Center). The existence of such an entity in an IBE scheme allows access to the encrypted information for other parties other than the intended recipient by construction: the KGC or any other entity that receives the cryptographic keys from the KGC may perform decryption. A system that permits other parties to have access to the private keys of the users is said to have key escrow abilities. The paper performs a brief analysis of the key escrow properties of IBE schemes and gives a practical example of communication protocol that improves the key escrow capabilities.