exists on tapes or disks. Everycomputer comes with acertain amount of physical
memory, usually referred to as main memory or RAM.
Non-heuristic
This method of scanning relies on specific virus signatures. The advantage of
the non-heuristic scan is that it is not fooled by what might seem to be a virus,
and does not generate false alarms.
Packed programs
A file in a compression format. Many operating systems and applicationscontain
commands that enable you to pack a file so that it takes up less memory. For
example, suppose you have a text file containing ten consecutive space
characters. Normally, this would require ten bytes of storage.
However, a program that packs files would replace the space characters by a
special space-series character followed bythe number of spaces being replaced.
In thiscase, the ten spaces would require only two bytes. This is just one packing
technique - there are many more.
Path
The exact directions to a file on a computer. These directions are usually
described by means of the hierarchical filing system from the top down.
The route between any two points, such asthe communicationschannel between
two computers.
Phishing
The act of sending an e-mail to a user falsely claiming to be an established
legitimate enterprise in an attempt to scam the user into surrendering private
information that will be used for identity theft. The e-mail directs the user to
visit a Web site where they are asked to update personal information, such as
passwords and credit card, social security, and bank account numbers, that
the legitimate organization already has. The Web site, however, is bogus and
set up only to steal the user’s information.
Polymorphic virus
A virus that changes its form with each file it infects. Since they have no
consistent binary pattern, such viruses are hard to identify.
Port
An interface on a computer to which you can connect a device. Personal
computers have various types of ports. Internally, there are several ports for
connecting disk drives, display screens, and keyboards. Externally, personal
computers have ports for connecting modems, printers, mice, and other
peripheral devices.
In TCP/IP and UDP networks, an endpoint to a logical connection. The port
number identifies what type of port it is. For example, port 80 is used for HTTP
traffic.
Glossary
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