DTIM (Delivery Traffic Indication Message) - A DTIM field is a countdown field informing clients of the next window for listening to broadcast and mul- ticast messages. When the AP has buffered broadcast or multicast messages for associated clients, it sends the next DTIM with a DTIM Interval value. AP Clients hear the beacons and awaken to receive the broadcast and multicast messages.
Dynamic IP Address - An IP address that is automatically assigned to a client station in a TCP/IP network, typically by a DHCP server. Network devices that serve multiple users, such as servers and printers, are usually assigned static IP addresses.
Encryption - A security method that applies a specific algorithm to data in order to alter the data's appearance and prevent other devices from reading the information.
Ethernet - IEEE standard network protocol that specifies how data is placed on and retrieved from a common transmission medium. Has a transfer rate of 10 Mbps. Forms the underlying transport vehicle used by several
Firewall - A firewall is a set of related programs, located at a network gateway server, that protects the resources of a network from users from other networks. (The term also implies the security policy that is used with the programs.) An enterprise with an intranet that allows its workers access to the wider Internet installs a firewall to prevent outsiders from accessing its own private data resources and for controlling what outside resources to which its own users have access.
Basically, a firewall, working closely with a router, examines each network packet to determine whether to forward it toward its destination.
Firmware - Code that is written onto
Fragmentation - Breaking a packet into smaller units when transmitting over a network medium that cannot support the original size of the packet.
FTP (File Transfer Protocol) - A protocol used to transfer files over a TCP/IP network (Internet, UNIX, etc.). For example, after developing the HTML pages for a Web site on a local machine, they are typically uploaded to the Web serv- er using FTP.
FTP includes functions to log onto the network, list directories and copy files. It can also convert between the ASCII and EBCDIC character codes. FTP oper- ations can be performed by typing commands at a command prompt or via an FTP utility running under a graphical interface such as Windows. FTP transfers can also be initiated from within a Web browser by entering the URL preceded with ftp://.
Unlike
Full Duplex - The ability of a device or line to transmit data simultaneously in both directions.
Gateway - A device that interconnects networks with different, incompatible communications protocols.
Half Duplex - Data transmission that can occur in two directions over a single line, but only one direction at a time.
Hardware - Hardware is the physical aspect of computers, telecommunica- tions, and other information technology devices. The term arose as a way to dis- tinguish the "box" and the electronic circuitry and components of a computer from the program you put in it to make it do things. The program came to be known as the software.
Hub - The device that serves as the central location for attaching wires from workstations. Can be passive, where there is no amplification of the signals; or active, where the hubs are used like repeaters to provide an extension of the cable that connects to a workstation.
ICQ - A conferencing program for the Internet that provides interactive chat,
IEEE (The Institute of Electrical and Electronics Engineers) - The IEEE describes itself as "the world's largest technical professional society, promoting
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