Remove key Escrow from the Identity-Based Encryption System

Abstract

Key escrow is an inherent property in the current proposed IdentityBased Encryption (IBE) systems. However the key escrow is not always a good property for all applications. In this paper, we present a scheme which removes the key escrow from the IBE system proposed by Bonch and Franklin, while at the same time maintaining some important properties of the IBE. We also present some cryptosystems based on our variant including a signature scheme and an authenticated key agreement. We finally show how to integrate our scheme into a hierarchial identity based public key encryption system.

E-Publishing and Collection Development: A Study of Current Practices and Status in Central Library, University of Delhi, New Delhi and Central Library, Jawaharlal Nehru University, New Delhi

“…These issues motivate the need for an efficient model to avoid such problems. Several approaches have been proposed to remove the key escrow problem [22,31,39,44,45,46,47], either by secure key issuing or user-chosen information. Nevertheless, the advantages come with some drawbacks.…”

“…To tackle this issue, certificate-less public key encryption [46] was introduced, which provides implicit authentication to the public key with user-chosen information. A new variant of IBE [31] was proposed, which uses a combination of the key issue by PKG and some information chosen by the user as a private key.…”

“…Chapter and certificate-less cryptography [31,39], where the user generates their own public and private keys without the involvement of a trusted third-party Certificate Authority.…”

Two-party authenticated key agreement in certificateless public key cryptography

“…It combines the advantages of the ID-PKC and the PKI. Since the concept of the CL-PKC is introduced, many certificateless public key encryption (CL-PKE) and signature schemes are proposed [3][4][5][6][7][8] . However, the key agreement in CL-PKC is seldom discussed.…”

Certificateless threshold cryptosystem secure against chosen-ciphertext attack

“…To solve this problem, in [11,26], Identity-based 0020-0255/$ -see front matter Ó 2007 Elsevier Inc. All public key cryptography (ID-PKC) is proposed, since the direct derivation of public keys from users' identities eliminates the needs for certificates. However, the inherent key escrow problem in ID-PKC is a great drawback [12,24]. To avoid the inherent key escrow of identity-based cryptography, in [3], Al-Riyami and Paterson introduce and make concrete the concept of Certificateless Public Key Cryptography (CL-PKC), a model which does not require certificates to guarantee the authenticity of public keys.…”