With the growth of the Internet, computer security has become a major concern for businesses and governments. They want to be able to take advantage of the Internet for electronic commerce, advertising, information distribution and access, and other pursuits, but they are worried about the possibility of being "hacked." At the same time, the potential customers of these services are worried about maintaining control of personal information that varies from credit card numbers to social security numbers and home addresses.
In their search for a way to approach the problem, organizations came to realize that one of the best ways to evaluate the intruder threat to their interests would be to have independent computer security professionals attempt to break into their computer systems. This scheme is similar to having independent auditors come into an organization to verify its bookkeeping records. In the case of computer security, these "tiger teams" or "ethical hackers" would employ the same tools and techniques as the intruders, but they would neither damage the target systems nor steal information. Instead, they would evaluate the target systems' security and report back to the owners with the vulnerabilities they found and instructions for how to remedy them.
An ethical hacker is a computer and network expert who attacks a security system on behalf of its owners, seeking vulnerabilities that a malicious hacker could exploit. To test a security system, ethical hackers use the same methods as their less principled counterparts, but report problems instead of taking advantage of them. Ethical hacking is also known as penetration testing, intrusion testing, and red teaming. An ethical hacker is sometimes called a white hat, a term that comes from old Western movies, where the "good guy" wore a white hat and the "bad guy" wore a black hat.
Successful ethical hackers possess a variety of skills. First and foremost, they must be completely trustworthy. While testing the security of a client's systems, the ethical hacker may discover information about the client that should remain secret. In many cases, this information, if publicized, could lead to real intruders breaking into the systems, possibly leading to financial losses. During an evaluation, the ethical hacker often holds the "keys to the company," and therefore must be trusted to exercise tight control over any information about a target that could be misused. The sensitivity of the information gathered during an evaluation requires that strong measures be taken to ensure the security of the systems being employed by the ethical hackers themselves: limited-access labs with physical security protection and full ceiling-to-floor walls, multiple secure Internet connections, a safe to hold paper documentation from clients, strong cryptography to protect electronic results, and isolated networks for testing.