TCP/IP header filtering blocks communication on the basis of the IP address and/or the port
number (which gives clues as to the type of Web service being accessed) contained in the header
of the data packet being sent.
Top-level domain the group of letters (usually two or three, but can include more) that follow
the final dot in a domain name. Example: in opennet.net, the top-level domain is .net.
URL (Uniform Resource Locator) is a string of characters that specify where a particular resource is
located online and how to retrieve it. Also known as a Web address.
User ID (User Identification) is a unique string of characters that identifies users of passwordprotected online services, such as e-mail or social networking sites.
VCD (Video Compact Disc) is a digital compression standard that enables the storage of video on a
Compact Disc.
VoIP (Voice over Internet Protocol) is a technology that allows for voice communication over the
Internet.
WAP (Wireless Application Protocol) is a global standard for the transfer of information without
using electrical conduits (wires). It allows for access to the Internet using mobile devices.
Warez (derived from the plural of ‘‘ware,’’ as in software) refers to copyrighted material that is
distributed in violation of copyright law.
White Hat a person who attempts to infiltrate information technology systems or networks in
order to expose weaknesses so they can be corrected by the systems’ owners. Also known as an
ethical hacker.
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Glossary of Technical Terms
number (which gives clues as to the type of Web service being accessed) contained in the header
of the data packet being sent.
Top-level domain the group of letters (usually two or three, but can include more) that follow
the final dot in a domain name. Example: in opennet.net, the top-level domain is .net.
URL (Uniform Resource Locator) is a string of characters that specify where a particular resource is
located online and how to retrieve it. Also known as a Web address.
User ID (User Identification) is a unique string of characters that identifies users of passwordprotected online services, such as e-mail or social networking sites.
VCD (Video Compact Disc) is a digital compression standard that enables the storage of video on a
Compact Disc.
VoIP (Voice over Internet Protocol) is a technology that allows for voice communication over the
Internet.
WAP (Wireless Application Protocol) is a global standard for the transfer of information without
using electrical conduits (wires). It allows for access to the Internet using mobile devices.
Warez (derived from the plural of ‘‘ware,’’ as in software) refers to copyrighted material that is
distributed in violation of copyright law.
White Hat a person who attempts to infiltrate information technology systems or networks in
order to expose weaknesses so they can be corrected by the systems’ owners. Also known as an
ethical hacker.
602
Glossary of Technical Terms