# Ringing - Discriminating (Optional)

## Description

Optional Discriminating Ringing lets you change the Discriminating Ringing patterns on ONS lines so that you hear internal ringing (1.0 s on and 3 s off) for both internal and external calls. The option is useful for automated machines (such as auto attendants and voice mail systems) that are unable to detect external ringing.

## Conditions and Feature Interactions

- Optional Discriminating Ringing applies only to devices that are connected to ONS line circuits.

- Other types of Discriminating Ringing (such as Callback, ACD help, Message Waiting, Dialog Port, Auto Answer, and Threshold Alert) take precedence.

- This feature does not apply to line appearances on multiline sets that are programmed as ONS stations.

- The ringback tones on incoming external calls are not altered even if the ringing cadence changes from external to internal.

- Optional Discriminating Ringing does not apply to Recorded Announcement Devices (devices programmed as RADs in the Class of Service).

- For calls to hunt groups, the ringing cadence is determined by the Class of Service of the first member of the group. Therefore, all members of a mixed group of telephones are rung with the same cadence as the first member.

- Ringing Discriminating (Optional) works across MSDN and DPNSS networks.

## Programming

- Class of Service Options form

- Enable ONS/OPS Internal Ring Cadence for External Callers.

## Device Support

ONS devices

## Operation

None

Related Topics

- Ringing - Discriminating