Glossary
Issue 3 June 2000
GL-17
Reactive Maintenance
Refers to detecting defects/failures and clearing them.
Remote
See FE (Far-End).
REN
Ringer Equivalent Number
Revertive
A protection switching mode in which, after a protection switch occurs, the equipment returns to the
nominal configuration (that is, the service equipment is active, and the protection equipment is
standby) after any failure conditions that caused a protection switch to occur clear or after any exter-
nal switch commands are reset. (See Non-Revertive.)
RGU
Ringing Generator Unit
Ring
A configuration of nodes comprised of network elements connected in a circular fashion. Under nor-
mal conditions, each node is interconnected with its neighbor and includes capacity for transmission
in either direction between adjacent nodes. Path switched rings use a head-end bridge and tail-end
switch. Line switched rings actively reroute traffic over a protection line.
Ring (0x1) Low Speed Interface
Formerly referred to as dual 0x1 or single 0x1. In ring applications, the DDM-2000 OC-3 and OC-12
Multiplexers use a 0x1 interface meaning both fibers carry service as opposed to a linear (1+1) low
speed interface where one fiber is used for service and the other for protection. See 1+1.
RPP
Reliability Prediction Procedure — Described in Telcordia Technologies TR-NWT-00032.
RT
Remote Terminal — An unstaffed equipment enclosure that may have a controlled or uncontrolled
environment.
RTAC
Lucent's Regional Technical Assistance Center (1-800-225-RTAC)
RZ
Return to Zero
S
SA
Service Affecting
SCADA
Supervisory Control and Data Acquisition
SD
Signal Degrade