Most Hotels will have some sort of telephone interface with IDPMS which may include PBX, Voicemail and Call Accounting. In order to communicate withe these interfaces, all telephone extensions need to be mapped in the Telephone Extension table in IDPMS. Telephone Extensions can be linked to a category (used to distinguish between Guest Phones and Admin phones for example. See Telephone Category
To access Telephone Extensions, go to Settings->Interfaces->Telephone Extensions:
To add an extension, select the add icon 
Extension - Enter the extension used in the phone management system (some hotels may have a prefix)
DID Number - If the phone system and interface support DID (Direct inward Dial) enter the full did number here.
Description- Enter a description for the extension (see examples below)
Room Number - Enter the room number as it is saved in IDPMS See Room Setup
Category - Select a category (see Telephone Category )
Ref Number - This field is used for the Alcatel interface only to enter a DID number.
Example
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