In telephony , the application of a signal to a line (a) to operate a line signal lamp or a supervisory signal lamp at a switchboard or (b) to ring a called receiver instrument. ( 188 )
RINGDOWN SIGNALING
Meaning of RINGDOWN SIGNALING in English
Telecommunication standard terms English vocab. Английский словарь стандартных телекоммуникационных терминов. 2012