# Local-only Directory Numbers - Description

Within a cluster, you can program directory numbers that only exist in the local databases of the member elements. These local-only directory numbers allow you to assign the same extension to a service or department that is local to the site supported by a cluster element. For example, you could assign local-only extension number 1000 to the security department at each site.

A local-only directory number is not listed in the Remote Directory Number forms of the cluster elements and is therefore not cluster dialable. A user on the same element can call a local-only directory number by just dialing its extension number. However, a user on a remote element cannot. To call a local-only directory number, a user on a remote element must dial the CEID digits followed by the local-only extension digits.

Figure 1 shows a simplified example of local-only directory numbers:

Local-only directory numbers are not listed in the Telephone Directory form or in the Remote Directory Numbers form. They only appear in the device-based form (for example, Multiline IP Sets) of the local element. As well, local-only numbers cannot be assigned a name (Last Name, First Name). Figure 2 illustrates how a local-only directory number is displayed in the forms of the cluster elements:

When you add a directory number to the Telephone Directory form, SDS writes the entry to the Remote Directory Number forms of the other elements in the cluster.

You add local-only directory numbers through device-based forms or through the User and Services Configuration form. These forms provide a check box that allow you to specify the directory number as local only. SDS shares the local-only designation to the other elements in the cluster. This reserves the directory number as a local-only number on the other cluster elements.

In MCD Release 4.0 and later, the System Administration Tool provides a Local-only Directory Number List form. In a RDN Synchronized cluster, this read-only form lists all the existing local-only directory numbers in the cluster.

Related Topics

- Local-only Directory Number - Conditions

- Local-only Directory Number - Programming