Glossary
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TEI
Terminal Endpoint Identifier (see Recommendations Q.920 and
Q.921)
synchronous function
Synchronous functions block an application or
process until the required task is successfully completed or a
failed/error message is returned.
T-1
A digital line transmitting at 1.544 Mbps over 2 pairs of twisted wires.
Designed to handle a minimum of 24 voice conversations or channels,
each conversation digitized at 64 Kbps. T-1 is a digital transmission
standard in North America.
termination condition
An event that causes a process to stop.
termination event
An event that is generated when an asynchronous
function terminates.
thread (Windows)
The executable instructions stored in the address space
of a process that the operating system actually executes. All processes
have at least one thread, but no thread belongs to more than one
process. A multithreaded process has more than one thread that are
executed seemingly simultaneously. When the last thread finishes its
task, then the process terminates. The main thread is also referred to as
a primary thread; both main and primary thread refer to the first thread
started in a process. A thread of execution is just a synonym for thread.
time slot:
In a digital telephony environment, a normally continuous and
individual communication (for example, someone speaking on a
telephone) is (1) digitized, (2) broken up into pieces consisting of a
fixed number of bits, (3) combined with pieces of other individual
communications in a regularly repeating, timed sequence (multiplexed),
and (4) transmitted serially over a single telephone line. The process
happens at such a fast rate that, once the pieces are sorted out and put
back together again at the receiving end, the speech is normal and
continuous. Each individual pieced-together communication is called a
time slot.
Two B Channel Transfer (TBCT)
Connects two independent B Channel
calls at an ISDN PRI user’s interface to each other at the PBX or CO.
The ISDN PRI user sends a Facility message to the PBX or CO
requesting that the two B Channel calls be connected. If accepted, the
user is released from the calls.