Glossary
GL-2 April 2001 8000-A2-GB26-50
CPU Central Processing Unit. The main or only computing device in a data processing system.
CRC Cyclic Redundancy Check. A mathematical method of confirming the integrity of received
digital data.
default route The address used for routing packets whose destination is not in the routing table. In
Routing Information Protocol (RIP), this is IP address 0.0.0.0.
DHCP Dynamic Host Configuration Protocol. A Microsoft protocol for dynamically allocating IP
addresses.
DHCP Relay Agent A system that detects and forwards DHCP discover or requ est mes sages to the appro priate
DHCP server.
DHCP Server A server which uses DHCP to allocate network addresses and deliver configuration
parameters to dynamically configured hosts.
domain A named group of machines on a network. In IP, a domain consists of a block of IP
addresses with similar prefixes.
downstream In the direction of the customer premises.
DSL Digital Subscriber Line. The non-loaded, local-loop copper connection between the
customer and the first node within the network.
DSL card Digital Subscriber Line Card. The prim ary card in the Hotwire DSLAM system. It h as one
Ethernet port and four DSL ports.
DSLAM Digital Subscriber Line Access Multiplexer. A platform for DSL modems that provides
high-speed data transmission with POTS over traditional twisted-pair wiring.
DSU/CSU Data Service Unit/Channel Service Unit. A device that combines the functions of a DSU a nd
a CSU. It connects Data Terminal Equipment to the digital network, protects the line from
damage, and regenerates the signal.
Enterprise MIB A MIB consisting of objects unique to a specific company’s devices.
Ethernet A type of network that supports high-speed communication among systems. It is a
widely-implemented standard for LANs. All hosts are connected to a coaxial cable where
they contend for network access using a Carrier Sense, Multiple Access with Collision
Detection (CSMA/CD) paradigm.
Ethernet address Another name for MAC address. The unique fix e d a ddre ss o f a pi ec e o f h ardware, normally
set at the time of manufacture and used in LAN protocols.
filter A rule or set of rules applied to a specific interface to indicate whether a packet can be
forwarded or discarded.
firmware Software that has been temporarily or permanently loaded into read-only memory.
FTP File Transfer Protocol. A TCP/IP standard protocol that all ows a user on one host to access
and transfer files to and from another host over a network, provided that the client supplies
a login identifier and password to the server.
full-duplex The capability to transmit in two directions simultaneously.
FUNI Frame based User-to-Network Interface.
gateway address The subnet that the end-user system is on. This address, which is the e1a address of the
domain, is used as the return address when the authentication server responds.
GranDSLAM A high-density DSLAM supporting a variety of DSL transport types and network services.
half-duplex The capability to transmit in two directions, but not simultaneously.