Agilent Technologies aurora Duet, User Manual

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Introduction
Issue 2 - 05/00 1 - 7
ISDN offers end-to-end (caller to receiver) digital
connectivity between terminal equipments (TEs) via
network terminating equipments (NTs) and digital
exchanges, both private and public.
Interface types
Your aurora
Duet
is designed to test the Basic Rate Interface
(BRI) which comprises three channels, collectively known
as 2B+D. The two B channels are reserved for data at
rates of up to 64kbps. The D channel is reserved for
control and signaling data at 16kbps, and may also be
used for X.25 packet-switched data.
Your aurora
Duet
is designed to test the Primary Rate
Interface (PRI), if fitted. This comprises 24 64kbps
timeslots, which together form the 1.544Mbps signal. 23
of the timeslots are the B-channels, reserved for data at
rates of up to 64kbps. Timeslot 24 is reserved for D
channel signaling.