Monday, December 29, 2003		Feature

THE intrusion in the cyber world is a serious problem. An intruder is a person who wants to make use of his/her intellect in a negative sense and illegally enters the codes or uses it maliciously. Intrusion clearly is undesirable. Hence appropriate defence mechanism is a must. In order to fight intrusion, the following are some commonly used techniques that cybermasters use:

1) Physical solution: In order to overcome the possibility of wiretapping, the transmission lines are enclosed in sealed tubes. These tubes contain chemically non-reactive argon gas. Alarm is triggered off whenever an intruder makes an attempt to tap the wire.

2) Cryptography: When a message has to travel through the communication network from the sender to the receiver, a popular technique called cryptography is used. It is a combination of encryption (conversion of sender’s message called plain text to secret message called cipher text) & decryption (conversion cipher text to plain text).

3) Firewalls: Another security measure used to secure corporate network from the intruder. It is a set of software and hardware that works by establishing a barrier between the corporate network and the Internet. It is an approach to implement a security policy that defines the service and access to be permitted to users.

4) Biometrics: Physical characteristics of employees dealing with computer systems are stored in the database. They require scanning and comparison of fingerprint impression, retina recognition, facial verification and voice recognition. Access is granted only when the characteristics tally with those stored in the database.