ZyWALL 10 Internet Security Gateway

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Countermeasures

Cracker

Cracker Tools

Cracking

Crossover Ethernet cable

Cryptoanalysis

CSU/DSU

DCE

Decryption

Denial of Service

DHCP

A string of characters saved by a web browser on the user's hard disk. Many web pages send cookies to track specific user information. Cookies can be used to retain information as the user browses a web site. For example, cookies are used to 'remember' the items a shopper may have in a shopping cart.

Techniques, programs, or other tools that can protect your computer against threats.

Another term for hackers. Generally, the term cracker refers specifically to a person who maliciously attempts to break encryption, software locks, or network security.

Programs used to break into computers. Cracker tools are widely

distributed on the Internet. They include password crackers, Trojans, viruses, war- dialers, and worms.

The act of breaking into computers or cracking encryption.

A cable that wires a pin to its opposite pin, for example, RX+ is wired to TX+. This cable connects two similar devices, for example, two data terminal equipment (DTE) or data communications equipment (DCE) devices.

The act of analyzing (or breaking into) secure documents or systems that are protected with encryption.

Channel Service Unit/Data Service Unit. CSUs (channel service units) and DSUs (data service units) are actually two separate devices, but they are used in conjunction and often combined into the same box. The devices are part of the hardware you need to connect computer equipment to digital transmission lines. The Channel Service Unit device connects with the digital communication line and provides a termination for the digital signal. The Data Service Unit device, sometimes called a digital service unit, is the hardware component you need to transmit digital data over the hardware channel. The device converts signals from bridges, routers, and multiplexors into the bipolar digital signals used by the digital lines. Multiplexors mix voice signals and data on the same line.

Data Communications Equipment is typically a modem or other type of communication device. The DCE sits between the DTE (data terminal equipment) and a transmission circuit such as a phone line.

The act of restoring an encrypted file to its original state.

Act of preventing customers, users, clients or other machines from

accessing data on a computer. This is usually accomplished by interrupting or overwhelming the computer with bad or excessive information requests.

Dynamic Host Configuration Protocol automatically assigns IP addresses to clients when they log on. DHCP centralizes IP address management on central computers that run the DHCP server program. DHCP leases addresses for a period of time, which means that addresses are made available to assign to other systems.

Glossary of Terms

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