 |
| |
|
|
|
|
Q
Q
See queue.
queue
Q.921/931
ITU-TS (formerly CCITT) Q Series Recommendations describing Lap- D, the
Layer Two protocol for an ISDN D-channel.
QA
See quality assurance
QAM
See quadrature amplitude modulation (QAM)
Qbit
See qualifier bit (Qbit)
QCIF
See quarter common intermediate format (QCIF)
QLLC
See Qualified Logical Link Control (QLLC)
QOS
See quality of service (QOS)
QRS
See quasi-random signal (QRS)
QRSS
See quasi random signal source (QRSS)
quad
An assembly of four-wire (two twisted-pairs) insulated conductors used
for home telephone installation.
quadrature amplitude modulation (QAM)
A combination of phase and amplitude modulation used for high-speed,
synchronous modems.
Qualified Logical Link Control (QLLC)
Routines to provide Synchronous Data Link Control.
qualifier bit (Qbit)
In X.25 networks, bit 8 in an octet of packet header. It is used to
indicate if a packet contains control information.
quality assurance
A formal approach to product development and delivery with the goal of
zero defects.
quality of service (QOS)
1) A measurement of the telephone service provided to a subscriber;
includes such factors as connection clarity or loudness. 2) The
statistical chart provided in the CascadeView statistics gathering
function; it details the lost packets and round trip delay
measurements.
quantization
The process that divides the continuous range of values of a signal
into nonoverlapping (but not necessarily equal) subranges. It then
assigns a discrete value of the output to each subrange. Whenever the
signal value falls within a given subrange, the output has the
corresponding discrete value.
quantization noise
Signal errors or noise that results from digitizing a continuously
variable signal.
quarter common intermediate format (QCIF)
A subset of the coded video signals transmitted when using the
International Consultative Committee for Telephone and Telegraph
(CCITT) Recommendation H.261 coding methods.
quartet signaling
Part of the 100BaseVG-AnyLAN proposed standard involving transmission
over all four wire pairs simultaneously in voice-grade unshielded
twisted pair (UTP) cable, expanding its capacity to 100Mbit/s.
quasi random signal source (QRSS)
A form of pseudo-random binary pulse sequence (PRBS).
quasi-random signal (QRS)
A digital test signal consisting of a bit sequence that approximates a
random signal.
query
The process by which a master station asks a slave station to identify
itself and indicate its status.
queue
1) A facility that stores transactions or event-oriented messages and
activates them for processing in a specific sequence such as first in
first out, priority, or event type. 2) A temporary delay in providing
service caused by the inability of the system provided to handle the
number of messages or calls attempted.
queuing
The act of holding incoming calls until an attendant, trunk, trunk
group or desired station is available. Synonym: camping
Quick Test
Automatic test procedures for testing DS1 or DDS circuits in REACT
2000.
QuickTime
Apple Computer's video environment (like Microsoft's Video For
Windows). QuickTime video files must be converted to *.AVI format to
run under Microsoft's Video For Windows. INDEO video is supported under
MacOS.
QWK
A type of mail packet.
|
