ABSTRACT
To protect digital assets and systems, the three major objectives of a network security system are to provide confidentiality, integrity and availability [92] to them. Intruders usually attempt to breach these measures mostly with malicious intentions. These days, people with such intentions can download many tools from the Internet and use them for such purposes. Due to the increased availability of sophisticated attack tools such as HOIC and LOIC [298], people can disrupt a network fairly easily. On the other hand, network administrators need other tools to defend their networks or to monitor and analyze the activities in the network. Without a good understanding of the attack behavior, it is very difficult to predict or detect an attack. Network security tools are used for purposes such as information gathering, victim identification, attack generation, packet capture, network traffic analysis and visualization of traffic behavior. With the increased sophistication and complexity of attacks, vigilant approaches to defend networks have become absolutely necessary. In this chapter, we provide a comprehensive survey and analysis of network security tools and their purposes, uses and effectiveness.
