ABSTRACT
The concept of public key cryptography is introduced by Diffie and Hellman. Different public key cryptography techniques have been used to implement digital signature. Tanwar et al. have worked on digital signature and multiple signatures to handle MITM attack on certificate authority. Moussa et al. reviewed the digital signature and multiple signatures. Digital signatures are of two types-single signature and multiple signatures. In 1984, Adi Shamir presented the notation of ID-based cryptography to tackle the issues of certificate-based cryptography. The main purpose of using CL-PKE is to resolve key escrow problem inherited from IBE without the use of certificates as in PKI. A digital signature is a cryptographic primitive that minimally produces the same security functions as a conventional signature such as authentication, integrity, confidentiality, and non-repudiation. The importance of authentication, verifying the identity of users and machines, becomes crucial when an organization opens its doors to the Internet.
