An Efficient Certificateless Arbitrated Signature Scheme for IoT Environments

Abstract

Recently, researches on lightweight cryptosystems for the IoT (Internet of Things) environment have been continuously conducted. Among the public key cryptosystems, ID-based cryptography has the advantage of verify the public key by using an identifier in the form of a public key. However, a key escrow problem occurs that requires the generation of both public and private key pairs in the Key Generation Center (KGC). To solve this problem, Certificateless Public Key Cryptography (CL-PKC), which is a public key cryptosystem without certificate was proposed. The CL-PKC is actively researched in various cryptography fields such as authentication, key agreement, signature, and encryption. In this paper, we analyze the CLS (Certificateless Signature), a signature scheme using CL-PKC for IoT environment. The existing CLS schemes may have problems such as public key replacement attack due to the weakness of the nonrepudiation function, so we propose a CL-based arbitrated signature scheme, CLAS.