G
LOSSARY
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ITU
International Telecommunication Union
ITU-T
Telecommunication Standardization Section of ITU
LAN
Local Area Network: A group of interconnected computers and support
devices.
MAC A
DDRESS
The physical layer address used to uniquely identify network nodes.
MTU
Maximum Transfer Unit. The maximum transfer unit for traffic crossing this
device. MTU should be set to a value that minimizes unnecessary
fragmentation and maximizes the transfer of large sequential data
streams.
NTP
Network Time Protocol: NTP provides the mechanisms to synchronize time
across the network. The time servers operate in a hierarchical-master-
slave configuration in order to synchronize local clocks within the subnet
and to national time standards via wire or radio.
P
ING
A utility used to determine whether a specific IP address is accessible. It
works by sending a packet to the specified address and waiting for a reply.
POTS
Plain Old Telephone Service. One of the services using voice band.
Sometimes used as a descriptor for all voice band services.
PPP
Point-to-Point Protocol. A protocol for connecting remote hosts to the
Internet using TCP/IP.
PPP
O
E
PPP over Ethernet. A protocol for connecting remote hosts to the Internet
over an always-on connection by simulating a dial-up connection.
PSTN
Public Switched Telephone Network.
Q
O
S
Quality of Service. A network protocol used to specify a guaranteed
throughput level. This protocol is often used by Internet service providers
to guarantee their customers a minimum end-to-end latency.
R
ATE
A
DAPTIVE
A DSL service that automatically adjusts the transmission rate depending
on line quality and loading to ensure data quality (such as, keeping within
a maximum error rate).
