Computer Security

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COMPUTER SECURITY

Computer security encompasses a wide range of technological issues. Computer security professionals work to combat hacking, which includes illegally accessing, manipulating, or destroying private information contained in computer networks. Computer security efforts typically involve the use of a combination of passwords, data encryption applications, virus detectors, and firewalls (hardware or software products that filter all information passed between a private intranet and other intranets or the Internet). Along with preventing hacking, computer security systems also offer detection programs, which allow network managers to determine if a security breach has happened and pinpoint the effects of the breach.

HISTORY OF COMPUTER SECURITY PROBLEMS

The issue of computer security first arose in the 1970s as individuals began to break into telephone systems. As technology advanced, computer systems became targets as well. The Federal Bureau of Investigation (FBI) made one of its first arrests related to computer hacking in the early 1980s. A group of hackers known as the 414s, named after their area code in Milwaukee, Wisconsin, were indicted for attacking 60 different computer systems including the Los Alamos National Laboratory and the Memorial Sloan-Kettering Cancer Center. Computer security breaches like these became increasingly commonplace throughout the 1980s, prompting the passage of the Computer Fraud and Abuse Act. The new legislation allowed more stringent punishments to be levied against individuals caught illegally abusing computer systems. Later in the decade, a 25-year-old hacker named Kevin Mitnick began tapping into the e-mail system used by computer security managers at both Digital Equipment Corp. and MCI Communications Corp. As a result, Mitnick was arrested and sentenced to one year in jail. Although a multitude of other hackers were brought to justice, many continued to operate, including one who successfully pilfered $70 million from the First National Bank of Chicago. Eventually, the Computer Emergency Response Team was established by the U.S. government to research the increasing number of computer security breaches.

Along with growth in hacking activity came the spread of computer viruses. Three of the most well known viruses—Cascade, Friday the 13th, and Stoned—all originated in 1987. When computer companies like IBM Corp. and Symantec Corp. began researching ways to detect and remove viruses from computers, as well as ways to prevent infection in the first place, virus writers began developing more elusive viruses. By 1991, more than 1,000 viruses had been discovered by computer security experts.

Computer security gaps were exposed at many major corporations and governmental bodies—including AT&T Corp., Griffith Air Force Base, NASA, and the Korean Atomic Research Institute—during the early 1990s. For example, an attack on AT&T's network caused the firm's long-distance service to temporarily shut down. During 1995, computers at the U.S. Department of Defense were attacked roughly 250,000 times. A study conducted by the Computer Security Institute that year determined that one in every five Web sites had been hacked. Also that year, Mitnick was arrested for computer fraud and once again sentenced to serve jail time. His offense that time included stealing software, product plans, and data from Motorola Inc., Sun Microsystems Inc., NEC Corp., and Novell Inc., costing the firms a combined total of nearly $80 million. Later in the 1990s, the Web sites of several federal agencies, including the U.S. Department of Justice, the U.S. Air Force, NASA, and the CIA, were defaced by hackers. In addition, the U.S. Bureau of Labor Statistics received a deluge of bogus requests for information. In 1998, the U.S. Department of Justice created the National Infrastructure Protection Center, charging it with task of safeguarding domestic technology, telecommunications, and transportation systems from hackers.

As the amount of commerce handled via the Internet grew, so did the number of malicious attacks. Hacking in 2000 increased 79 percent over 1999 figures, according to a report released by the FBI's Computer Emergency Response Team (CERT). Even leading Web sites such as Yahoo!, America Online, eBay, and Amazon.com were exposed as vulnerable, costing the firms millions of dollars and undermining the already tenuous confidence online shoppers had in the security levels of these sites. Eventually, one of the key perpetrators in many of these attacks, a 16-year-old Canadian boy operating under the name Mafiaboy, was arrested, and authorities discovered he also had broken into the computer networks at Harvard and Yale Universities. While on parole, Mafia-boy was prohibited from using the Internet or shopping at stores that sold computers; only when supervised by a teacher at school, could he use a computer.

TYPES OF COMPUTER SECURITY PROBLEMS

As the need for high levels of computer security became increasingly apparent to business owners, many began to earmark additional dollars for security technology and for staff to oversee security measures. By then, the most popular form of attack was the denial of service (DOS), which simply overloads a network system until it crashes. For example, a DOS attack on online auction giant eBay in February 2000, which involved sending the site a barrage of fake requests for Web pages, caused eBay's system to crash. Similarly, CERT's Web site was shut down for two days after a myriad of fake information requests overloaded its system. A DOS known as a worm began gaining significant media attention in 2001. In July of that year, the worm entitled Code Red began attacking Microsoft Internet Information Server systems. Code Red infected servers running Windows NT 4, Windows 2000, Windows XP, and IIS 4.0, and it replaced Web site content with the phrase "Welcome to www.worm.com Hacked by Chinese!" The damage caused by the Code Red worm was estimated at $1.2 billion. As Alex Salkever stated in a May 2001 BusinessWeek Online article, these types of attacks are commonplace. "According to a study released last week by scientists at the University of California-San Diego's supercomputing facility, more than 4,000 DOS attacks happen each week. The most sophisticated and serious last for days as dozens, hundreds, even thousands, of hijacked 'zombie' computers pour forth an unceasing barrage of Web-page requests, all unbeknownst to the machines' owners."

Mail bombs behave in the same manner. However, they target a network's mail server with the goal of shutting down e-mail service by overloading the system. Hackers targeting networks may also attempt to gain access to secure areas containing sensitive data, such as credit card numbers or social security numbers. A security breach of this type can cause serious damage to a business or institution since data files can be not only copied, but also deleted. AOL became victim to this type of attack in the late 1990s when teenagers from Wichita, Kansas, successfully hacked AOL's network and used the credit card numbers they found there to purchase video games.

Other types of attacks on computers include viruses and Trojan horses. A virus is a program designed to affix itself to something within a computer, such as a file or boot sector, and begin reproducing itself. A file virus, like the Friday the 13th virus that originated in the late 1980s, attaches itself to an executable file—one that controls applications—and begins overwriting parts of the file. Roughly two-thirds of all virus attacks involve boot sector viruses, which are harder to detect than file viruses because they make no discernible impact on a system until they actually attack. Boot sector viruses are quite often designed to overwrite an entire hard drive. A virus also might be designed to use all of a computer's resources and prompt it to crash. Two of the most popular transmission methods for viruses are floppy disks and e-mail. For example, the "I LOVE YOU" and the "Love Bug" viruses that appeared in May of 2000 were circulated via e-mail. The resulting damage to individuals, companies, and institutions was judged to be nearly $10 billion. Like viruses, logic bombs attack computer files and hard drives. Quite often, hackers use a Trojan horse to gain initial access to computers. Trojan horses are disguised as harmless programs, but once executed might release a virus or even a worm.

COMPUTER SECURITY PROGRAMS

The first major computer security program was developed late in the 1970s, when three Massachusetts Institute of Technology (MIT) graduates created RSA encryption technology. The data-scrambling program eventually was used in leading computer platforms such as Microsoft Windows, and well-known software applications like Quicken and Lotus Notes. Computer security primarily remained a governmental concern throughout the 1970s and 1980s. The rise of corporate networks, along with the growth of e-commerce, prompted more widespread concern about computer security in the 1990s.

Companies using computers began linking them together via networks in the 1980s, and many of those networks were then linked to the Internet in the 1990s. Companies with many geographically dispersed offices were able to use the Internet to link networks. Similarly, those with employees on the road could grant off-site workers access to the intranet. In fact, according to PC Week writer Jamie Lewis, one of the Internet's most important benefits to businesses was its ability to "simplify the often expensive and complex tasks of giving remote users access to corporate networks and of linking remote sites." The fact that one of the largest problems hindering that task was security encouraged the development of virtual private network (VPN) technology, which combined "tunneling, authentication, and encryption technologies to create private sessions over the public Internet."

Another major boon of the Internet revolution, the rise of e-commerce, also brought with it major security headaches. To make a purchase online, shoppers were normally required to input their credit card numbers. Eventually, even tax returns became something consumers could transmit via the Internet. To protect this sensitive data, companies began seeking sophisticated security systems. Most online merchants began using data encryption programs, such as Secure Sockets Layer (SSL), Secure Electronic Transactions (SET), and Data Encryption Standard (DES) to protect personal information transmitted over the Web.

The most popular method of computer protection among home computer users is anti-virus software. Companies including Symantec Corp. and Network Associates offer anti-virus applications that scan every file on a disk or on a computer's hard drive for infected material, alerting users if corrupted files are found. To keep pace with a the continual development of new viruses, many computer security software firms allow users to periodically download from their Web sites software upgrades which recognize newer viruses. Firewalls, once mainly used for computer networks, also have become popular with home users, particularly those who use cable modems and digital subscriber lines for uninterrupted online connections.

Other software options—mainly used to protect larger computer systems—include Intrusion Detection Systems (IDS), content filtering software, sand-boxing software, and behavior analysis software. IDS is considered one of the best protection methods for large networks. With an IDS in place, system administrators can monitor network requests and detect large-scale malicious attacks. Content filtering software is advanced anti-virus software that reads compressed files and allows IT managers to set specific filtering parameters to block threatening e-mail. Sandboxing software protects against malicious codes by creating an isolated space within a computer where suspicious code can run, before it has a chance to interact with the main operating system. Still in its infancy in 2001, behavior analysis software protects computer systems by monitoring entire networks and checking every command of all operations.

Because many malicious hackers eye security systems not as a deterrent but as a mere obstacle to overcome, the numbers of computer security breaches may continue to rise. However, as long as hacking attacks persist, both individuals and businesses will continue to invest in programs and software designed to protect systems from unwanted intruders. In fact, while many computer industry experts believe that avoiding all hacking activity is nearly impossible, Datamonitor predicts that spending related to computer security will grow from $10.6 billion in 2001 to $22.3 billion in 2004.