Reference Guide

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CPU
Central Processing Unit . The part of a computer that processes information.
CPUs are composed of a control unit and an ALU.
D
DHCP Client
A device using DHCP to obtain configuration parameters, such as a network
address.
DHCP Snooping
DHCP Snooping expands network security by providing firewall security
between untrusted interfaces and DHCP servers.
DSCP
DiffServe Code Point (DSCP) . DSCP provides a method of tagging IP
packets with QoS priority information.
Domain
A group of computers and devices on a network that are grouped with
common rules and procedures.
Duplex Mode
Permits simultaneous transmissions and reception of data. There are two
different types of duplex mode:
• Full Duplex Mode — Permits for bisynchronous communication, for
example, a telephone. Two parties can transmit information at the same
time.
• Half Duplex Mode — Permits asynchronous communication, for
example, a walkie-talkie. Only one party can transmit information at a
time.
Dynamic VLAN Assignment (DVA)