ADTRAN 1204002L2, TSU IQ+ user manual Isdn

Appendix D. Glossary

ISDN

integrated services digital network. A network architecture that enables end-to- end digital connections. The network supports diverse services through inte- grated access arrangements and defines a limited set of standard, multipurpose interfaces for equipment vendors, network providers, and customers. Inter- working with a public switched telephone network is retained.

LAN

local area network. A privately owned network that offers high-speed commu- nications channels to connect information processing equipment in a limited geographic area.

LBO

line buildout. The introduction of gain or loss in a signal to optimize the signal level for a receiver.

local loop

In telephony, the wire pair that connects a subscriber to a phone company end office. Four-wire local loops are common and are used on T1 facilities.

local loopback

A type of test used to verify the operation of the local terminal equipment, the CSU, and the connection between the two units. The signal from the DTE is looped back by the CSU and is sent back to the DTE.

loopback

The technique for testing the processing circuitry of a communications device. May be initiated locally or remotely via a telecommunications circuit. Device being tested will echo back received test data. The results are compared with the original data.

LOS

loss of signal. Defined as a line state in which no pulses are received for 175 bit positions.

MIB

management information base. A database of network management informa- tion used by SNMP.

modem

The equipment that connects DTE to analog (voice) communications.

61200275L1-1 TSU IQ+ User Manual D-9