Practical Identity-Based Encryption (IBE) in Multiple PKG Environments and Its Applications

Abstract. Identity-based encryption (IBE) schemes are usually used in multiplePKG environments — on the one hand, each administrative domain (e.g., a relatively small and close organization) maintains its own private key generator (PKG); on the other hand, encryption across domains becomes a prevalent requirement. In this paper, we present a new IBE scheme using bilinear pairings. Compared with the famous IBE scheme of Boneh and Franklin, we show that ours is more practical in the multiple-PKG environment. We prove that our scheme meets chosen ciphertext security in the random oracle model, assuming the intractability of the standard Bilinear Diffie-Hellman (BDH) problem. As an application of our IBE scheme, we also propose an escrowed ElGamal scheme which possesses certain good properties in practice.

• Type: Journal
• Year: 2007
• Where: CORR
• Authors: Shengbao Wang
• Keywords: CORR 2007, Education, Famous Ibe Scheme, Ibe Scheme, Private Key Generator