Abstract
Technology has enhanced the jeopardy of misuse of individual confidential data and
identity theft attacks, where securing the content of communication and confidentiality has
become one of the chief requirements. Here Cryptography operates as the cornerstone of
computer and communications security. Certificateless cryptography, together with digital
signatures, is the best solution for achieving fundamental security, i.e., confidentiality, data
integrity, non-repudiation, and authentication. Correspondingly, certificateless cryptography
(CLS) abolishes certificate management problems and the key escrow problems of public-key
cryptography (PKC) and identity-based cryptography (IBC). CLS is the optimum combination
of PKC and ID-based PKC, hence making it more efficient. Many signature schemes rely on
certificateless schemes (CLS) and are formed using bilinear pairing and the MTP hash
functions. An MTP (map-to-point) hash function and elliptic curve bilinear pairing are lavish
procedure schemes, and they enhance computation expenses in the schemes and are timeconsuming. In contrast, pairing-free CLS schemes rely on elliptic curve cryptography (ECC)
and have comparatively less computational cost, providing the desirable time requirement and
making the scheme more efficient. In this chapter, we have done a survey of various pairingfree CLS schemes and compared them with each other. We have analyzed the performance
evaluation of various schemes’ security and efficiency. Some are even observed to be
precarious under various attacks.