An Efficient Certificateless Arbitrated Signature Scheme for IoT Environments

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.