
Glossary
interface
A common boundary between two systems over which the
ISDN
Integrated services digital network. A network architecture that enables
leased line
A telecommunication facility or link reserved for the exclusive use of one custom- er. Also called a dedicated line.
leased service
The exclusive use of any channel or combination of channels designated to a sub- scriber.
local loop
In telephony the wire pair that connects a subscriber to a phone company end of- fice, typically containing two wires.
loopback
A diagnostic procedure where data is sent to the device being tested, and the out- put of the device is fed directly back to its input, looped around, and the returning data is checked against that which was sent.
loopback test
A test typically run on a
master clock
The source of timing signals, or the signals themselves, which all network stations use for synchronization.
message
The Layer 3 information that is passed between the CPE and SPCS for signaling.
multiplexing
The combining of multiple data channels onto a single transmission medium. Any process through which a circuit normally dedicated to a single user can be shared
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