Introduction to Computer Security

As with any business asset, information systems hardware, software, networks, and data resources need to be protected and secured to ensure quality, performance, and beneficial use. Security management is the accuracy, integrity, and safety of information resources. When effective security measures are in place, they can reduce errors, fraud, and losses.

There are intentional and unintentional threats. Unintentional threats are considered to be human error, environmental hazards, and computer failures. Most people don't purposely cause harm. Intentional threats refer to purposeful actions resulting in the theft or damage of computer resources, equipment, and data. Intentional threats include viruses, denial of service attacks, theft of data, sabotage, and destruction of computer resources. Most intentional threats are viewed as computer crimes when executed.

To protect computer networks and resources, there are a number of security measures individuals and organizations can take to protect their assets, such as encryption, firewalls, anti-virus, anti-spyware, passwords, back-ups, and biometric security.

Security Threats

Bill has a great deal of knowledge concerning computers and computer networks. He works for a large technology company and has become disillusioned with the organization. He dislikes what they stand for and the way they conduct business. He's tired of his job, and he can't stand his boss. Before Bill quits his job, he decides to cause a bit of mayhem with the computer network. He has all the skills needed to easily hack into his organization's computer network and do all the damage he wants.

Bill would be considered a cracker. A cracker is a term used to describe someone who intentionally breaches security to break into someone else's computer or network for a malicious purpose. Many people mistakenly use the term hacker to describe someone who breaks into computer systems for their own agenda, usually to cause harm. Popular media has fueled this misconception. A hacker is actually a term used to describe a computer programmer with advanced knowledge of computers and computer networks. A hacker finds weaknesses in a computer or a network so that they can be corrected.

The Internet increases the vulnerability of information systems and networks so that they can be used to facilitate attacks by criminals and crackers. Bill starts his assault with a denial of service (DoS) attack. A DoS attack floods a network with traffic, rendering the network useless to its intended users. The attack will either force the target network to reset or consume its resources so that it is unable to provide its intended service. Bill plans his attack for a busy Monday morning to make the impact harsher. Recently, major banks, such as Bank of America, Wells Fargo, and PNC, have experienced cyber-attacks. Crackers used a denial of service attack method. While private information was not stolen, the attacks still posed a security threat and inconvenience for customers and the organization.

Next, Bill uses computer viruses to unsuspectingly attack the computer systems and cause harm. A virus is a program that infects a computer without the user's knowledge. It can replicate itself and easily spread from one computer to another. Bill develops a computer virus that will erase files and lock up company computers. He spreads it through a mass company email. The virus will attach itself to other computer programs, causing them to become viruses themselves. For instance, it could attach itself to a spreadsheet file. Anytime that spreadsheet is opened, the virus has the opportunity to replicate and spread. Email is a prime medium for spreading viruses. Emails with attachments can contain unwelcomed viruses that, when opened, will infect the user's computer.

Email is an effective tool for spreading computer viruses.

Bill knows his previous attacks have caused some damage for the organization. He wants to do even more damage to the company. He hacks into the accounting files and bank account information and changes some of the data. Data tampering refers to entering false, fabricated, or fraudulent data into the computer or changing or deleting existing data. This type of threat is orchestrated by insiders. It can cost organizations a great deal of money.

One of the fastest-growing crimes has been identity theft. Identity theft is the stealing of another person's social security number, credit card number, or other personal information for the purpose of borrowing money, making purchases, and running up debts. Since many private organizations and governments keep information about individuals in accessible databases, there is endless opportunity for thieves to retrieve it and misuse the information. Since Bill dislikes his boss so much, he obtains his corporate credit card information through the network and fraudulently uses the credit card to make extravagant purchases.

Security Defenses

Because of the large number of threats, a great deal of defensive strategies and tools have been developed. Bill may have to contend with some of these as he attacks his organization's computer network, but as an insider, he will likely have the knowledge needed to bypass them. This is why insiders can be so dangerous to computer security.

Bill's boss, John, takes security seriously. He relies upon encryption for any data he sends to others. Encryption is a method for securing data by using special mathematical algorithms to convert the data into scrambled code before transmission. The data is decoded when an authorized user accesses it. There are a number of software encryption standards, but the two main ones are RSA by RSA Data Security and PGP, or Pretty Good Privacy, available on the Internet.