ISDN NETWORK TERMINATION - NT 1 (Model: NT-B)

Telenet’s ISDN Network Termination for basic rate access is the main gate to the world of ISDN. It enables subscribers to use services such as high-speed transmission of data, text and video signals in digital format over an access line in addition to voice transmission. It is a link between the subscriber line (U Interface) and the user Interface to the network (S/T interface). A maximum of 8 terminal units can be connected to the S/T interface.

The digital transmission format used offers the subscriber the possibility of access to two independent Basic Channels (B Channels) each with 64 Kbit/s and one 16 Kbit/s Signaling Channel (D), to be transmitted. The terminals connected to S/T for any two ISDN services can use both B channels simultaneously. The associated Signaling information and various service features are transmitted over the D Channel. This result in a Transmission speed of 144 Kbits/s for both transmits and receives direction.

The NT1 is installed at the end of the public transmission line coming from the ISDN switch of the local exchange and converts the 2-wire duplex U interface into the 4wire double simplex subscriber S/T interface.

Features:

• Up to 8 access sockets can be connected to the S/T interface via a 4-wire bus.
• Two services like telephony and Data transmission can operate simultaneously.
• Data rate of 144 Kbps is available to the customer at the S/T interface.
• It has three bus configurations, which have different coverage ranges.
• Point to Point.
• Point-to-Multipoint: Short passive bus.
• Point-to-Multipoint: Extended passive bus.
• Has four operating modes depending on whether transmission is active or inactive and whether the integrated power supply is working or not
• Echo cancellation at the U interface ensures that Data Signals are transmitted bidirectionally.
• The interface modules operate in the automatic mode.
• The U interface module recovers clock synchronization signal, monitor transmission errors and initiate appropriate actions.
• In the event of a long-term short circuit, the power supply module is auto switched off and resumes operation automatically with only a delay of few seconds.
• The design is in compliance with ITU/CCITT/ANSI/ETSI and industry standard 2B1Q line code for the Uinterface.
• It is easy to install at the user’s premises and can be installed in a wall-mounted cabinet or used as a desktop version.
• Testing and operation configurations can be adjusted quickly by means of switches and jumpers.

Technical Data:

The technical data of the NT1 is as under