An arrangement that permits sequential connection of tie trunks between PBX and Centrex® locations by using tandem operation . Note: Tandem operation permits two or more dial tie trunks to be connected at a tandem center to form a through connection.
TANDEM TIE TRUNK NETWORK (TTTN)
Meaning of TANDEM TIE TRUNK NETWORK (TTTN) in English
Telecommunication standard terms English vocab. Английский словарь стандартных телекоммуникационных терминов. 2012