Administrator's Guide

Glossary and abbreviations
555-233-5061986 Issue 5 October 2002
NQC
Number of queued calls
NSE
Night-service extension
NSF
Network-specific facility
NSU
Network sharing unit
null modem cable
Special wiring of an RS-232-C cable such that a computer can talk to another computer (or to a printer) with-
out a modem.
NXX
Public-network office code
O
OA
Operator assisted
occurrence
See appearance.
OCM
Outbound Call Management
offered load
The traffic that would be generated by all the requests for service occurring within a monitored interval, usu-
ally one hour.
ONS
On-premises station
OPS
Off-premises station
OPX
Off-premises extension
OQT
Oldest queued time
OSHA
Occupational Safety and Health Act
OSI
Open Systems Interconnect
OSS
Operations Support System