Справочник Пользователя для Netopia r9100

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2  User’s Reference Guide
byte: A group of bits, normally eight, which represent one data character.
CallerID: See CND.
CCITT (Comite Consultatif International Telegraphique et Telephonique): International Consultative 
Committee for Telegraphy and Telephony, a standards organization that devises and proposes recommenda-
tions for international communications. See also ANSI (American National Standards Institute).
CHAP (Challenge Handshake Protocol): A method for ensuring secure network access and communications.
Class A, B, and C networks:  The values assigned to the first few bits in an IP network address determine 
which class designation the network has. In decimal notation, Class A network addresses range from 1.X.X.X to 
126.X.X.X, Class B network addresses range from 128.1.X.X to 191.254.X.X, and Class C addresses range 
from 192.0.1.X to 223.255.254.X. For more information on IP network address classes, see 
client: An intelligent workstation that makes requests to other computers known as ser vers. PC computers on 
a LAN can be clients.
clustering:  A feature that clusters remapped network numbers into a range of sequential network numbers.
CNA (Calling Number Authentication): A security feature that will reject an incoming call if it does not match 
the Calling Number field in one of the Netopia ISDN Router’s connection profiles.
CND (Calling Number Delivery):  Also known as caller ID, a feature that allows the called customer premises 
equipment (CPE) to receive a calling par ty’s director y number during the call establishment phase.
community strings:  Sequences of characters that ser ve much like passwords for devices using SNMP. 
Different community strings may be used to allow an SNMP user to gather device information or change device 
configurations.
CRC (Cyclic Redundancy Check): A computational means to ensure the integrity of a block of data. The 
mathematical function is computed, before the data is transmitted at the originating device. Its numerical value 
is computed based on the content of the data. This value is compared with a recomputed value of the function 
at the destination device.
DCE (Data Communications Equipment): Term defined by standards committees that applies to 
communications equipment, typically modems or printers, as distinct from other devices that attach to the 
network, typically personal computers or data terminals (DTE). The distinction generally refers to which pins in 
an RS-232-C connection transmit or receive data. Also see DTE.
DDP (Datagram Delivery Protocol):  Defines socket-to-socket deliver y of datagrams over an AppleTalk internet.
default zone:  When a Phase II EtherTalk network includes more than one zone, all routers on that network 
must be configured to assign one of these zones as a default zone. The default zone is temporarily assigned to 
any Phase II EtherTalk node that hasn’t chosen a zone. The user may choose another zone by opening the 
Network Control Panel, selecting the correct physical connection, and then choosing a zone in the scrolling field 
displayed.
DHCP (Dynamic Host Configuration Protocol): A ser vice that lets clients on a LAN request configuration 
information, such as IP host addresses, from a ser ver.
DNS (Domain Name Service): A TCP/IP protocol for discovering and maintaining network resource information 
distributed among different ser vers.
download: The process of transferring a file from a ser ver to a client.