# Advanced Automatic Route Selection Description

## Description

Advanced Automatic Route Selection (ARS) selects the most cost-effective route available to the required destination using day, time zones, route plans and ARS assignment that have been programmed.

To select the most cost-effective route, the ARS examines the digit string dialed, selects the route, and then modifies the digit string to use the route. This routing process is to the extension user. Advanced ARS can also be used in private networks, for alternative routes or route barring.

The routing of an external call from a system depends on:

- route availability (with alternative routing when the first choice is busy)

- least cost routing based on time of day and day of week (when more than one route exists)

- call barring (allowing extensions to call certain numbers or groups of numbers).

## Numbering Plans

This feature is compatible with any numbering plan in any public network.

## Public Networks

A number of public networks exist in the United Kingdom. Within these networks customers can access several routes, including Exchange Lines, Private Circuits, High Speed Digital Systems (such as MEGASTREAM), and microwave radio links. Each of these routes has a different tariff, so ARS can allow the user to make substantial savings.

Access to the public networks can be either by direct or indirect connection. A direct connection can be made by copper cable, optical fiber cable or by a microwave link, all supplied by the network operator. An indirect connection can be made via the British Telecom network and an access code and personal identification number.

To determine which routing options are best suited to any given system, a traffic survey should be completed prior to installation. The Traffic Measurement and System Message Detail Recording (SMDR) features of the system allow the use of trunk routes to be monitored once the system is installed, so they can be modified if traffic demands change.

NOTE: The emergency number (999) should NOT be routed indirectly through a public network.

## Exchange Lines

Exchange Lines allow telephone users to call any number within the national and international network without operator assistance. Connections are made over standard routes and are charged on a time basis at a rate which varies with distance, time-of-day, and day of the week. Charging information is given in the local telephone directory.

## Private Circuit Working

Private Circuits provide a fixed connection between two systems. The telephone network operator makes a periodic charge for each Private Circuit that is based on the distance between the two ends. This charge does not vary according to the use of the circuit.

Related Topics

- Advanced Automatic Route Selection Example

- Advanced Automatic Route Selection Features

- Advanced Automatic Route Selection Programming

- Automatic Route Selection (Basic)