ADTRAN 4200659L8 out-of-band, point-to-point, protocol, Pstn, red alarm, remote configuration

Appendix D. Glossary

NRZ

Non return to zero. A mode in which the digital level is low for a 0 bit and high for a 1 bit, and does not return to zero between successive 1 bits.

out-of-band

Signaling that is separated from the channel carrying information (voice, data, video, etc.). Typically the separation is accomplished by a filter. The signaling includes dialing and other supervisory signals.

point-to-point

Type of communications link that connects a single device to another single device, such as a remote terminal to a host computer.

POP

Point of presence. Physical place within a LATA (local access and transport area) where a long distance carrier or a cellular provider interfaces with the network of the local exchange carrier (LEC). A POP is usually a building serving as the point of termination which houses switches and transmission equipment.

protocol

A set of rules controlling the orderly exchange of information between stations in data communications networks or systems.

PSTN

Public switched telephone network. Usually refers to the world-wide voice tele- phone network available for public use.

red alarm

Unframed all ones signal (keep alive signal). A red alarm is declared on detec- tion of LOS or OOF not caused by an alarm indication signal (AIS) that persists for more than two seconds.

remote configuration

A feature designed into ADTRAN products that allows remote units to be con- figured from a local unit or a VT 100 compatible terminal.

61200659L1-1 MX2800 STS-1 User Manual D-9