Vodavi NomadIP, Руководство пользователя

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Glossary
107
December, 2005 Vodavi Telenium IP Product Guide
mobility ▪ presence ▪ collaboration ▪ convergence
Authentication The process of determining whether someone or something is, in fact, who or what it is declared
to be. In private and public computer networks (including the Internet), authentication is
commonly done through the use of logon passwords.
Backbone A backbone is a larger transmission line that carries data gathered from smaller lines that
interconnect with it.
Binary The number system that uses only zeros and ones. A computer only uses the binary number
system in its internal calculations.
Bit A bit (short for binary digit) is the smallest unit of data in a computer. A bit has a single binary
value, either 0 or 1. There are eight bits in a byte. The value of a bit is usually stored as either
above or below a designated level of electrical charge in a single capacitor within a memory
device.
BOOTP BOOTstrap Protocol. A BOOTP server maintains a database of IP-to-MAC address mappings and
inform each BOOTP client what its IP address is it powers up. See also DHCP.
BRI Basic Rate Interface ISDN provides a channelized 2 B channel and one D channel circuit clocked at
144Kbps. he bearer, or B Channels, are used to transport data between two locations. Each B-
Channel carries 64Kbps of data. The D channel, which is used to communicate between the carrier
and premise equipment, is a 16Kbps channel.
Bridge A data communications device that connects two or more network segments and forwards packets
between them.
Broadband Telecommunication in which a wide band of frequencies is available to transmit information.
Because a wide band of frequencies is available, information can be multiplexed and sent on many
different frequencies or channels within the band concurrently, allowing more information to be
transmitted in a given amount of time. DSL service and cable modem Internet service are
examples of broadband data.
Broadcast Broadcast packets are those that are intended to reach every node on a network. For example, a
PC requesting an IP address from a DHCP server sends a broadcast packet because it does not
know the address of the DHCP server. Compare with Unicast.
Byte A unit of data that is eight binary digits long.
Cable Modem A cable modem is a device that enables packet data service (Internet service) to be delivered over
a cable TV line. The data rate is typically 1.5 Mbps or higher.
Cache A mapping obtained at a client’s request which is retained for a predetermined period to cut down
on repeated queries across the network for the same information. Network devices utilize a cache
in conjunction with the ARP and DNS protocols.
Class of
Service Class of Service (CoS) is a way of managing traffic in a network by grouping similar types of traffic
(for example, e-mail, streaming video, voice, large document file transfer) together and treating
each type as a class with its own level of service priority.
Client A device, or an application on a device, which sends commands or requests to a server.
Clustering A method of enabling multiple computer servers to act as a single server. Clustering may be
accomplished via software or hardware.
Codec Also called vocoder. Software which converts analog sound or video signals into digital code and
vice versa.
CPE Customer Premise Equipment