Symantec 460R - Gateway Security Administrator's Manual page 168

168 Glossary
bandwidth
blended threat
bps (bits per second)
broadcast
broadcast storm
buffer overflow attack
cable
client
client computer
communications
communications device
communications session
computer
computer group
configuration
content filtering
data rate
data transfer
data transmission
data-driven attack
denial of service (DoS)
attack
The amount of data transmitted or received per unit time. In digital systems, bandwidth is proportional to the data
speed in bits per second (bps). Thus, a modem that works at 57,600 bps has twice the bandwidth of a modem that
works at 28,800 bps. See also bps.
An attack that uses multiple methods to transmit and spread. The damage caused by blended threats can be rapid
and widespread. Protection from blended threats requires multiple layers of defense and response mechanisms.
A measure of the speed at which a device such as a modem can transfer bits of data.
To simultaneously send the same message to all users on a network.
A network condition in which broadcast Ethernet or IP packets multiply through switches and cause congestion.
Symantec Gateway Security 400 Series appliances offer broadcast storm protection to prevent the condition from
affecting normal network traffic.
An attack that exploits a known bug in one of the applications running on a server. This then causes the application
to overlay system areas, such as the system stack, thus allowing the attacker to gain administrative rights. In most
cases, this gives the attacker complete control over the system. Also called stack overflow.
A group of wires that are enclosed in a protective tube. Usually this is an organized set of wires that correspond to
specific pins on a 9- or 25-pin connector located at each end. A cable is used to connect peripheral devices to each
other or to another computer. In remote computing, this can refer to a cable that is used to connect a computer to a
modem, or a cable that connects two computers directly, which is sometimes called a null modem cable.
A requesting program or user in a client/server relationship. For example, the user of a Web browser is effectively
making client requests for pages from servers all over the Web. The browser itself is a client in its relationship with
the computer that is getting and returning the requested HTML file.
A computer that is running a client program. In a network, the client computer interacts in a client/server
relationship with another computer that is running a server program.
The transfer of data between computers by means of a device such as a modem or cable.
A modem, network interface card, or other hardware component that enables remote communications and data
transfer between computers. Also called connection device.
The time during which two computers maintain a connection and, usually, are engaged in transferring information.
A defined entity on the LAN or WLAN that firewall rules and security policies are applied to. Not necessarily a PC, a
computer can be any Ethernet-enabled device like a printer or scanner. See also computer group.
A group of LAN or WLAN Ethernet devices that firewall rules and security policies are applied to. For example, all
local printers may be in a computer group that has all outbound Internet communication blocked. See also computer.
A collection of settings that a software feature uses.
The use of content-based filters that are applied to traffic passing through a security gateway. You can filter content
based on protocol type, subject matter, MIME types, URLs, and filename extensions.
The speed at which information is moved from one location to another. Data rates are commonly measured in
kilobits (thousand bits), megabits (million bits), and megabytes (million bytes) per second. Modems, for example, are
generally measured in kilobits per second (Kbps). See also bandwidth, bps.
The movement of information from one location to another. The transfer speed is called the data rate or data
transfer rate.
The electronic transfer of information from a sending device to a receiving device.
A form of intrusion in which the attack is encoded in seemingly innocuous data. It is subsequently executed by a user
or other software to actually implement the attack.
A type of attack in which a user or program takes up all of the system resources by launching a multitude of requests,
leaving no resources and thereby denying service to other users. Typically, denial of service attacks are aimed at
bandwidth control.