ABSTRACT : However, a full general overview of network security and cryptography is furnished and diverse algorithms are This paper directs to allow a broad critical review of network protection and cryptography, with especial reference to digital key signature. Network security and cryptography is a branch of knowledge too varied to coverage almost how to protect data in digital form and to allow protection avails. discussed. A elaborated critical review of the content of network security and cryptography in digital key signature is then acquainted. The aim of a digital key signature is to allow a way for an entity to attach its identity element to a piece of fact. The basal attacks on digital key signature was reexamined. The 1st method constituted the RSA key signature scheme, which continues nowadays among the most pragmatic and flexible methods available. Fiat-Shamir signature schemes, DSA and associated signature schemes are two additional processes looked back. Digital key signature have a lot of application program in data protection, including authentication, information integrity, and non-repudiation made up reviewed.