Cyber attacks against Google have recently been in the news.Yahoo and other companies have been attacked, as well. Microsoft, in turn, has gone to court to attack a network of malicious botnets. With all this activity in the cyber security arena, it is worth investigating which companies are at the forefront of the battle against hackers. With a wave of concern over hacking attempts, there should be some good investment candidates in the network security sector. Background -- When I talk about security I'm talking about intrusion detection and protection. An intrusion-prevention system (IPS) is an inline security device that performs deep-packet inspection to identify and block malicious traffic. IPSs are considered an improvement over intrusion-detection systems (IDS), which are passive devices that simply identify an attack but take no action to block it. IPSs are designed to respond in real time to attacks by dropping data packets deemed malicious. There several ways that...