Past few years the use of Internet and its applications has increased to a great extent. There is also an enormous growth in the establishment of computer networks by large, medium and small organizations, for data transfer and information exchange. Due to this huge growth, incidents of cyber-attacks and security breaches have also increased. Data on a network is transferred using protocols such as hyper text transfer protocol, which is very vulnerable. Many types of malicious contents are hidden in packets that are transferred over a network or system, which may can to get it slow, crash or buffer overflow etc. Thus it is very important to secure networks from such types of attacks.