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Glossary
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email (electronic mail)
finger
firewall
firewall rule
fragment
hacker
HTML (Hypertext Markup Language)
inbound communication
IP (Internet Protocol)
A method of exchanging messages and files with other people via computer networks. A popular protocol for sending email is SMTP (Simple Mail Transfer Protocol). Popular protocols for receiving email are POP3 (Post Office Protocol 3) and IMAP4 (Internet Message Access Protocol 4).
A command in some operating systems that requests network user account information.
A security system that uses rules to block or allow connections and data transmissions between your computer and the Internet.
A set of parameters that specifies a type of data packet or network communication and an action to perform (permit it or block it) when it is found.
An IP packet that has been split into two or more parts, or fragments. When the size of an IP packet exceeds the maximum frame size of a network that it crosses, the packet must be divided into smaller packets, or fragments.
A person who attempts unauthorized access of other people’s computers for the purpose of obtaining information from, or doing damage to, those computers.
A standard language for documents on the World Wide Web. Codes inserted in a text file instruct the Web browser on how to display a Web page’s words and images for the user, and define hypertext links between documents.
An attempt by an external computer to open a connection to your computer. The connection can be used to send data to and from your computer.
The essential protocol by which data is sent from one computer to another on the Internet. IP routes packets to the appropriate destinations.