# Connecting to the telephone network

BRI access provides the means to connect one or more devices to the network. Depending on your requirements, you can connect the AG 2000-BRI interfaces to a T0 trunk for a point-to-point configuration or to an S0 trunk for a point-to-multipoint configuration.

Warning: | Important safety notes for telephony connections Allow only qualified technical personnel to install this board and associated telephone wiring. Make sure the PC chassis is grounded through the power cord or by other means before connecting the telephone line. Never install telephone wiring during a lightning storm. Never install telephone jacks in wet locations. Telephone companies provide primary lightning protection for their telephone lines. However, if a site connects to private lines that leave the building, make sure that external protection is provided.

As shown in the following illustration, AG 2000-BRI boards have four RJ-45C connectors. Shielded cables are also available with AG 2000-BRI boards.

AG 2000-BRI end bracket with four RJ-45C connectors

The current version of the AG 2000-BRI board supports the terminal (TE) and the network (NT) modes. All wiring configurations refer to the ITU-T Recommendation I.430.

## Connecting to a T0 trunk

A typical point-to-point configuration is shown in the following illustration. In this case, the maximum distance between the network equipment (NT1) and the terminal (TE) is 1 kilometer.

Connection at the T0 interface

In Europe, the NT1 equipment is usually handled by the network provider.

## Connecting to an S0 trunk

The following illustration shows a typical point-to-multipoint configuration (up to eight terminals) where two main topologies are supported (also called S-bus).

### Short passive bus

With this configuration, up to eight TEs can be connected anywhere on the bus. The bus length is limited to 200 meters (refer to the following illustration):

Connection at the S0 interface-short passive bus configuration

### Extended passive bus

With this configuration, up to eight TEs can be connected, but only at the far end of the bus from the NT side. In this case, the length of the bus can be from 500 meters up to 1 kilometer (refer to the following illustration).

Connection at the S0 interface-extended passive bus configuration