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ISDN PRI Installation
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NTD12 Dual-port DTI/PRI card
description and installation
NT5D12 Dual-port DTI/PRI (DDP) card overview
The NT5D12 is a dual-port 1.5 DTI/PRI card (the DDP firmware functions in
DTI or PRI mode) integrating the functionality of two QPC472 DTI/QPC720
PRI cards and one QPC414 ENET into one card. The NT5D12 occupies a
single Network shelf slot and provides two DTI/PRI network connections, an
optional connection to an external D-Channel Handler, the QPC757
D-Channel Handler Interface (DCHI) or NT6D80 Multi-purpose Serial Data
Link (MSDL), and an optional plug-on NTBK51AA Downloadable
D-Channel daughterboard (DDCH.)
The NT5D12 DDP card supports all features (except the echo canceller and
protocol conversion) of the QPC720. In addition, it maintains the backward
compatibility of QPC720.
The NT5D12 DDP card hardware design uses a B57 ASIC E1/T1 framer. The
carrier specifications comply with the ANSI TI.403 specification. The
NT5D12 provides an interface to the 1.5 Mbps external digital line either
directly or through an office repeater, Line Terminating Unit (LTU), or
Channel Service Unit (CSU).