Buch1 > Functions, Uses, Concepts > Sub-System Operation > Setting Options
Setting Options
The PBX supports sub-system operation on a higher-level PBX, for example to connect an external office to headquarters.
Requirements:
• At least one free internal VoIP channel for the main PBX
• At least one free external VoIP channel for the subordinate PBX
Proceed as follows to configure the main PBX:
• Creating VoIP subscribers in the main PBX.
-Using the Configuration Manager (page Subscriber (scr.) > Phone numbers >  New)
* Note: The corresponding subscribers in main and subordinate PBX must have the same internal phone number.
-Module/Port: VoIP
-Device type: Standard VoIP phone
• Switching internal phone on for each subscriber.
-Using the Configuration Manager (page Subscriber (scr.) > Phone numbers > Configure > Settings)
-Exchange line request: Internal phone
Proceed as follows to configure the subordinate PBX:
• Creating subscribers in the subordinate PBX.
-Using the Configuration Manager (page Subscriber (scr.) > Phone numbers >  New)
* Note: The corresponding subscribers in main and subordinate PBX must have the same internal phone number.
• Switching direct exchange line phone on for each subscriber.
-Using the Configuration Manager (page Subscriber (scr.) > Phone numbers > Configure > Settings)
-Exchange line request : Direct exchange line phone
* Note: If the PBs are to be linked via a STUN server, set STUN server for the connection of external VoIP subscribers (page Administration > VoIP configuration.
• Make the following settings for the provider „Auerswald“.
-Using the Configuration Manager (page Public switched tel. networks > VoIP > Provider > Configure)
-Domain : IP address of main PBX
-Registrar : IP address of main PBX
-Sub-system operation
-Format of called phone number: Send as dialled
-Format of own phone number: Without country code (e. g. 05306...)
-Number presentation type: In the display text
-Method of number presentation suppression: Anonymous
• Configure a VoIP account for each subscriber.
-Using the Configuration Manager (page Public switched tel. networks > VoIP > Accounts >  New)
-Provider name: Auerswald
-Account name : Freely selectable name for identification of the account
-Connection type: PTMP connection
-Use
• Entering access data for each VoIP account subscriber.
-Using the Configuration Manager (page Public switched tel. networks > VoIP > Accounts > Configure)
-Exchange line access number (account number): 2- to 4-digit number
-User name: Internal phone number of the VoIP subscriber of the main PBX
-Password: PIN of the VoIP subscriber of the main PBX
* Note: We recommend to use a password for remote extensions.
-Account has emergency call ability disabled:
• Assigning each subscriber to the corresponding account.
-Using the Configuration Manager (page Public switched tel. networks > VoIP > Accounts > Configure >  New)
-Multiple subscriber number (MSN): Subscriber‘s phone number
• Switching on automatic assignment of the preferred exchange lines.
-Using the Configuration Manager (page Subscriber (scr.) > Phone numbers > Configure > Exchange line settings > Preferred exchange line business: Automatica assignment)
• Creating call distribution.
-Using the Configuration Manager (page Public switched tel. networks > Call distribution)
-Call distribution for: VoIP PTMP connections and account name
-Internal no. | name: Assign internal phone numbers one-to-one to MSNs