Instruction manual

GLOSSARY
Immediate-Start Tie Trunk
After establishing a connection with the distant switching system for an outgoing call, the
system waits a nominal 65 milliseconds before sending the digits of the called number. This
allows time for the distant system to prepare to receive the digits. Similarly, on an incoming
call, the system has less than 65 milliseconds to prepare to receive the digits.
Inside Call
A connection between two parties within the system.
Intercept Tone
An alternating high and low tone; indicates a dialing error or denial of the service
requested.
Interchangeable Numbering Plan Area (INPA)
Allows interchangeable central office and area codes.
Interface
A common boundary between two systems or pieces of equipment.
Internal Call
A connection between two users within the system. Same as an inside call.
I-Use LED
A red LED on a multiline voice terminal that lights to show which call appearance will be
selected when the handset is lilted or which call appearance is active when a user is off-
hook.
LDN: (Listed Directory Number)
LED: (Light Emitting Diode)
LMA (Loss of Multiframe Alarm)
Loss of Multiframe Alarm applies only to Common Channel signaling and indicates the near
end is unable to synchronize to the multiframe pattern received in the 24th DS0 channel.
LOS (Loss of Signal Alarm)
LOS alarm occurs when the pulse density on the DS1 falls below the level where clock can
be derived from the bit stream.
November 1995
9-9