Agilent Technologies auroraSonata, User Manual

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aurora Sonata Hand Held ISDN Tester—User Guide
A4-6 427869
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In telecommunications, this is a predefined pattern of bits
which is used in a protocol to define an event—e.g. the
beginning of a transmitted frame.
Frame
A series of bits, arranged in a pattern, used for
transmitting information over a channel. Different
protocols have different frame structures.
Frequency
The number of cycles of an alternating signal over a given
period of time (usually 1 second). Measured in Hertz.
HDLC
High level Data Link Control. The original bit oriented
protocol.
HLC
Higher Layer Compatibility.
Integrated
A circuit, usually made of a semi-conductor, which is
Circuit
constructed as an assembly of electronic elements in a
single structure.
ISO
The International Standardisation Organisation. A
voluntary activity of the national standardisation
organisations of each member country. The ISO works
closely with the ITU-T in the development of standards.
ITU
International Telecommunications Union.
ITU-T
A committee of the ITU, organised into study groups that
set standards or recommendations for
telecommunications. The ITU-T has representatives from
world governments. Formerly known as the CCITT.
Kbps
Kilobits per second.
LAN
Local Area Network. A high speed link, usually carrying
data, connecting several communicating devices over a
relatively small geographical area.
LAPD
Link Access Procedure for a D Channel.
Layer
In the OSI model, a layer is a collection of related
functions within a communications system with a defined
service interface to layers above and below.