time interval
Issue 1.0 May 2003
429
T1
A digital transmission standard that in North America carries traffic at the DS1 rate of
1.544 Mbps. A T1 facility is divided into 24 channels (DS0s) of 64 kbps. These 24
channels, with an overall digital rate of 1.536 Mbps, and an 8-kbps framing and
synchronization channel make up the 1.544-Mbps transmission. When a D-channel
is present, it occupies channel 24. T1 facilities are also used in Japan and some
Middle-Eastern countries.
TAAS
Trunk Answer from Any Station
TABS
Telemetry asynchronous block serial
TAC
Trunk-access code
tandem switch
A switch within an electronic tandem network (ETN) that provides the logic to
determine the best route for a network call, possibly modifies the digits outpulsed,
and allows or denies certain calls to certain users.
tandem through
The switched connection of an incoming trunk to an outgoing trunk without human
intervention.
tandem tie-trunk network
(TTTN)
A private network that interconnects several customer switching systems.
TC
Technical consultant
TCM
Traveling class mark
TDM
See
time-division multiplexing (TDM)
on page 429.
TDR
Time-of-day routing
TEG
Terminating extension group
terminal
A device that sends and receives data within a system. See also
administration
terminal
on page 387.
tie trunk
A telecommunications channel that directly connects two private switching systems.
time-division multiplex
(TDM) bus
A bus that is time-shared regularly by preallocating short time slots to each
transmitter. In a PBX, all port circuits are connected to the TDM bus, permitting any
port to send a signal to any other port.
time-division
multiplexing (TDM)
Multiplexing that divides a transmission channel into successive time slots. See also
multiplexing
on page 417.
time interval
The period of time, either one hour or one-half hour, that BCMS measurements are
collected for a reports.