w w w . i j c s t . c o m InternatIonal Journal of Computer SCIenCe and teChnology 775 Abstract Now days Information Security is the prime concern of technocrats. The rapid growth and widespread use of electronic data processing and electronic business conducted through the Internet, along with numerous occurrences of international terrorism, fueled the need for better methods of protecting the computers and the information they store, process and transmit. The academic disciplines of computer security, information security and information assurance emerged along with numerous professional organizations – all sharing the common goals of ensuring the security and reliability of information systems. In this paper we are carrying out the comparative study of different digital signature based security mechanism proposed earlier and come up with the conclusion that the latest digital signature scheme based on Iterated Function System (IFS) is better in security and other aspects.