.. puter become more and more important and helpful. You can input a large amount of information or data in a small memory chip of a personal computer. The hard disk of a computer system is liked a bank. It contained a lot of costly material.
Such as your diary, the financial situation of a trading company or some secret military information. Therefore, it just like hire some security guards to protect the bank. A computer security system can use to prevent the outflow of the information in the national defense industry or the personal diary in your computer. Nevertheless, there is the price that one might expect to pay for the tool of security: equipment ranging from locks on doors to computerized gate-keepers that stand watch against hackers, special software that prevents employees to steal the data from the company’s computer. The bill can range from hundreds of dollars to many millions, depending on the degree of assurance sought. Although it needs to spend a lot of money to create a computer security system, it worth to make it. It is because the data in a computer can be easily erased or destroyed by a lot of kind of hazards.
For example, a power supply problem or a fire accident can destroy all the data in a computer company. In 1987, a computer centre inside the Pentagon, the US military’s sprawling head quarters near Washington, DC., a 300-Watt light bulb once was left burning inside a vault where computer tapes were stored. After a time, the bulb had generated so much heat that the ceiling began to smelt. When the door was opened, air rushing into the room brought the fire to life. Before the flames could be extinguished, they had spread consume three computer systems worth a total of $6.3 million.
Besides those accidental hazards, human is a great cause of the outflows of data from the computer. There have two kind of people can go in the security system and steal the data from it. One is those trusted employee who is designed to let in the computer system, such as programmers, operators or managers. Another kind is those youth amateurs who experiment at night —- the hackers. Let’s talk about those trusted workers.
They are the groups who can easily become a criminal directly or indirectly. They may steal the information in the system and sell it to someone else for a great profit. In another hand, they may be bribed by someone who want to steal the data. It is because it may cost a criminal far less in time and money to bride a disloyal employee to crack the security system. Beside those disloyal workers, hacker is also very dangerous.
The term “hacker” is originated at M.I.T. as students’ jargon for classmates who doing computer lab in the night. In the beginning, hackers are not so dangerous at all. They just stole some hints for the test in the university. However, in early 1980s, hacker became a group of criminal who steal information from other commercial companies or government departments.
What can we use to protect the computer ? We have talked about the reasons of the use of computer security system. But what kind of tools can we use to protect the computer. The most common one is a password system. Password are a multi-user computer system’s which usual used for the first line of defense against intrusion. A password may be any combination of alphabetic and numeric characters, to maximum lengths set by the e particular system.
Most system can accommodate passwords up to 40 characters. However, a long passwords can be easily forget. So, people may write it down and it immediately make a security risk. Some people may use their first name or a significant word. With a dictionary of 2000 common names, for instance, a experienced hacker can crack it within ten minutes.
Besides the password system, card-keys are also commonly used. Each kind of card-keys can employ an identifying number or password that is encoded in the card itself, and all are produced by techniques beyond the reach of the average computer criminal. Three types of card usually used. They are magnetic watermark, Optical memory card and Smart card. However, both of the tools can be easily knew or stole by other people. Password are often forgotten by the users and card- key can be copied or stolen.
Therefore, we need to have a higher level of computer security system. Biometric device is the one which have a safer protection for the computer. It can reduce the probability of the mistaken acceptance of outsider to extremely low. Biometric devices are instrument that perform mathematical analyses of biological characteristics. However, the time required to pass the system should not be too long.
Also, it should not give inconvenience to the user. For example, the system require people to remove their shoes and socks for footprint verification. Individuality of vocal signature is one kind of biometry security system. They are still in the experimental stage, reliable computer systems for voice verification would be useful for both on-site and remote user identification. The voice verifier described here is invented by the developmental system at American Telephone and Telegraph. Enrollment would require the user to repeat a particular phrase several times.
The computer would sample, digitize and store each reading of the phrase and then, from the data, build a voice signature that would make allowances for an individual’s characteristic variations. Another biometric device is a device which can measuring the act of writing. The device included a biometric pen and a sensor pad. The pen can converts a signature into a set of three electrical signals by one pressure sensor and two acceleration sensors. The pressure sensor can change in the writer’s downward pressure on the pen point. The two acceleration sensor can measure the vertical and horizontal movement.
The third device which we want to talk about is a device which can scan the pattern in the eyes. This device is using an infrared beam which can scan the retina in a circular path. The detector in the eyepiece of the device can measure the intensity of the light as it is reflected from different points. Because blood vessels do not absorb and reflect the same quantities of infrared as the surrounding tissue, the eyepiece sensor records the vessels as an intricate dark pattern against a lighter background. The device samples light intensity at 320 points around the path of the scan , producing a digital profile of the vessel pattern.
The enrollment can take as little as 30 seconds and verification can be even faster. Therefore, user can pass the system quickly and the system can reject those hackers accurately. The last device that we want to discuss is a device which can map the intricacies of a fingerprint. In the verification system, the user places one finger on a glass plate; light flashes inside the machine ,reflect off the fingerprint and is picked up by an optical scanner. The scanner transmits the information to the computer for analysis. Although scientist have invented many kind of computer security systems, no combination of technologies promises unbreakable security. Experts in the field agree that someone with sufficient resources can crack almost any computer defense.
Therefore, the most important thing is the conduct of the people. If everyone in this world have a good conduct and behavior, there is no need to use any complicated security system to protect the computer.