User's Manual

General Information Guide - Release 3.1
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ISDN Primary Rate Interface
ISDN Primary Rate Interface (PRI) has become the most cost-effective enterprise solution for IT
managers responding to increased demands for remote LAN access, Internet and intranet access,
off-site desktop and group video conferences, and a host of other inbound and outbound data
applications.
All inbound and outbound services that are usually obtained by using different trunk types (such as
INWATS, OUTWATS, FX, Tie, and DID) can be accessed with a single ISDN trunk; as a result, the
number of trunks can be reduced by 10 to 15 percent. On outbound calls, the system requests the
required service from the Network. The trunk takes on the requested characteristics for the duration
of the call.
At the same time, ISDN supports enhanced voice communications capabilities. These capabilities
include Caller Line Identification Delivery (CLID), Automatic Number Identification (ANI), and Dialed
Number Identification Service (DNIS). These options allow you to know who is calling and facilitate
call center and CTI applications, fast call set-up, call-by-call, and Min/Max for reduced trunking. ISDN
delivers the highest degree of voice clarity of any transmission medium available.
R2
R2 Support
The 3300 R2 NSU provides access to the R2 National Public Switched Telephone Network (PSTN)
with MF-R2 digital trunk signaling. The 3300 R2 NSU supports the CCITT Blue Book, Volume VI,
Fascicle VI.4, Specifications of Signaling System R2, Recommendations Q.44o to Q.490 (with the
exception of Q.479 Echo Suppression, Q.490 Test Calls and international signals).
Many countries use R2 signaling but do not adhere to the CCITT recommendations in their entirety.
The 3300 ICP is completely flexible and supports regional variations of the R2 protocol. Line
signaling, tone interpretation, and timing parameters for the converter can be adapted to suit any
national or regional requirement. For example
• Line signaling features allow you to program up to four bits to define the incoming and outgoing
patterns for line signals such as Idle and Answer
• Register signaling features allow you to program the type of address signaling termination
(signaled or timed) and whether signaling should be fully-compelled or semi-compelled. These
features allow the individual definition of each register signaling tone.