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 (Subscriber (scr.) > Phone numbers > 
New)
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 (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 (Subscriber (scr.) > Phone numbers > New)
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 (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 (Administration > VoIP configuration.•Make the following settings for the provider „Auerswald“.
−Using the Configuration Manager (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 (Public switched tel. networks > VoIP > Accounts > New)
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 (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 (Public switched tel. networks > VoIP > Accounts > Configure > New)
New)−Multiple subscriber number (MSN): Subscriber‘s phone number
•Switching on automatic assignment of the preferred exchange lines.
−Using the Configuration Manager (Subscriber (scr.) > Phone numbers > Configure > Exchange line settings > Preferred exchange line business: Automatica assignment)
•Creating call distribution.
−Using the Configuration Manager (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