With the outcome of smart technologies from the World Wide Web and the emergence of ecommerce applications and social networks, organizations across the world generate a large amount of data daily. Information security is the most extreme basic issue in guaranteeing safe transmission of data through the web. Also network security issues are now becoming important as society is moving towards digital information age. As more and more users connect to the internet it attracts a lot of cyber-attacks. Its required to protect computer and network security i.e. the critical issues. The pernicious hubs make an issue in the system. It can utilize the assets of different hubs and safeguard the assets of its own. In this paper we provide an overview on Network Security and various techniques through which Network Security can be enhanced i.e. Cryptography.