"Access" is defined in Section 2(1)(a) of the Information Technology Act as "gaining entry into, instructing or communicating with the logical, arithmetical, or memory function resources of a computer, computer system or computer network". Unauthorised access would therefore mean any kind of access without the permission of either the rightful owner or the person in charge of a computer, computer system or computer network. Thus not only would accessing a server by cracking its password authentication system be unauthorised access, switching on a computer system without the permission of the person in charge of such a computer system would also be unauthorised access.
Key Terms in this Chapter
Trojan: A Trojan (aka Trojan horse) is a software program in which harmful or malicious code is contained within another program. When this program executes, the Trojan performs a specific set of actions, usually working toward the goal of allowing itself to persist on the target system.
Hacking: Hacking is commonly used today to refer to unauthorized access to a computer network. Breaking into a computer system or network is simply one of many forms of hacking.
Cracker: This was coined by hackers in defence against journalistic misuse of the term “hacker.” The term “cracker” reflects a strong revulsion at the theft and vandalism perpetrated by cracking rings.
Rootkit: The primary purposes of a rootkit are to allow an attacker to maintain undetected access to a compromised system. The main technique used is to replace standard versions of system software with hacked version, and install backdoor process by replacing one or more of the files, such as ls, ps, netstat, and who.
Virus: A virus is a piece of software which is capable of reproducing itself and causing great harm to files or other programs on the same computer. A true virus cannot spread to another computer without human assistance.
Eavesdropping: Eavesdropping is the intercepting of conversations by unintended recipients. One who participates in eavesdropping is called an eavesdropper.
Back Door: In the security of a system, this is a hole deliberately left in place by designers or maintainers. May be intended for use by service technicians. However, it is more commonly used now a days to refer to software, which has been maliciously loaded by persons remotely in order to allow them to enter the system through a ‘back door’ at an opportune time.
Worm: A worm is a software program capable of reproducing itself that can spread from one computer to the next over a network. Worms take advantage of automatic file sending and receiving features found on many computers.