Network Configuration

Network Infrastructure

There are several possibilities to integrate pascom into your network. The below documentation applies to both our virtual phone systems as well as our hardware based PBX solutions.

Integration into an Existing Company Network

Integrating pascom directly into small to medium sized business networks is relatively straight forward and requires only a minimum of changes to the existing infrastructure. An existing DHCP server can either be used by pascom and all connected devices or you can configure pascom as the DHCP server for the complete network (s. DHCP Server Configuration).

Illustration - Integrated Network Infrastructure

If you are connecting either Snom, Yealink, Auerswald or Aastra IP telephones to your pascom, you can also use them as switches to connect desktop computers or additional end user devices in order to further simplify your network. This will reduce cabling and is in particularly useful in weaker network environments.

Illustration - Integrated Network Structure with Telephones

Separating Telephony and Company Networks

To provide the highest flexibility and operational reliability, pascom can be operated from within a dedicated network separated from the company network. This setup is beneficial in many ways:

  • Problems with Quality of Service and conflicts with existing network services can be avoided; telephone traffic is not compromised by load peaks in the company network.
  • Access to the telephony network can be controlled via a firewall.
  • No changes to the DHCP service on the company network are needed, as pascom can provide its own DHCP service for the telephone network.
  • In a separate telephony network, Snom, Yealink, Auerswald, OpenStage and Aastra phones can be powered by a PoE (PowerOverEthernet) switch. When connected up to an uninterruptable power supply (UPS), phone calls can still be made in the event of a power failure.

There are several ways by which to separate the networks. In all scenarios, access to the telephone network is provided in order to allow configuration of both pascom and connected devices via the network.

Separation via Phone System Interfaces

In order to separate both networks, different network interfaces, which are available within pascom, can be used for each network. The telephony appliance is assigned an IP address within the networks and will therefore be able to communicate with the phones on the telephone network as well as with devices on the company network.

Illustration - Separated Network Structure via PBX

The network settings of the pascom appliance can be configured according to your requirements; network traffic can be subjected to firewall policies or otherwise restricted through routing settings on the server.

Separation Using a Gateway

Alternatively, you can use an existing security gateway to integrate the telephone network. In this case, all routing and filtering tasks are handled by your existing firewall.

Illustration - Separated Network Structure via a Gateway

DHCP Server Configuration

pascom phone systems require a DCHP server in order to be able to assign all connected IP telephones with IP addresses and provisioning URLs. For this purpose, our PBX software includes an integrated DHCP server which can be used. Alternatively, you can use your already existing DHCP server.

Integrated DHCP-Server

Using pascom’s integrated DHCP Server has numerous advantages:

  • The configurations server will already have been automatically provided to the telephones.
  • Should you assign a telephone with a fixed IP address within the PBX web UI, the reservation will be automatically entered into the DHCP server settings.
  • The DHCP server can be setup to assign IP addresses to the telephones to be provisioned and as such ignore all other requests.

The DHCP server can be activated within the Web UI Appliance > Services > and selecting the DHCP-Server menu tab.
When activating the DHCP server, it will be necessary to select some standard configuration options

Status Description
Yes The DHCP server will assign IP addresses for the selected network
Yes, phones only The DHCP server will assign IP addresses only for pascom PBX provisioned IP Endpoints within the selected network.
No The DHCP server is deactivated
Additional Settings:
from area… to area Defines the range of IP address which can be assigned to devices. The DHCP server will then assign addressing starting with the last available IP Address.
Domain-Name, Domain-Name-Server, Gateway Parameters which are passed on the requesting device.

Using a Windows DHCP Server

When using the Windows DHCP server or a DHCP server follows the same options pattern, you will need to activate DHCP option 66 and replace with your PBX server’s IP address. This option tells the telephone sending the request where it can download the appropriate configuration file.

Phone Manufacturer Option 66 Option 67
Auerswald <MACADR>
Siemens OpenStage

It is possible to run the integrated pascom PBX DHCP server and the Windows DHCP server within the same network. In this case, the PBX assigns IP addresses and options for configuration server to the phones, while the Windows DHCP server assigns IP addresses to all other devices. The Windows DHCP server needs to be configured in a way that ensures it ignores requests from your IP telephones. Every MAC address starts (first six characters) with a manufacturer specific identifier which can be used to identify the device manufacturer. Under the Windows DHCP Server Filter option, these MAC address identifiers will need to be added to the Disallow filter.

Phone Manufacturer MAC-Adresses
Snom 00-04-13-*-*-*
Aastra/Mitel 00-08-5D-*-*-*
Yealink 00-15-65-*-*-*
Auerswald 00-09-52-*-*-*
Siemens OpenStage 00-01-E3-*-*-*

Once the addresses have been added, the filter must be activated.

Using a Linux DHCP Server

Under a Linux DHCP server, option 66 is called tftp-server-name. This option tells the telephone sending the request where it can download the appropriate configuration file. Please note that depending on the manufacturer of the phone, different values will need to be set as follows:

Phone Manufacturer tftp-server-name filename
Auerswald <MACADR>
Siemens OpenStage

You will need to update your Linux DHCP Configuration, which can be done by simply adding the following line (our example is for Yealink Telephones):

option tftp-server-name "";

Multi-Location Networking, HomeOffices and Mobile Users

As the workplace is becoming increasingly mobile, communication is often passed through public or private networks. pascom integrates seamlessly into this concept of a distributed network architecture. pascom provides users with a transparent overview of the network infrastructure, ensuring a logically interconnected network in terms of telephone and data traffic. Separation into virtual networks (VLAN) is also supported by pascom.

Illustration - Multi-location Networking

Branch offices can have their own telephony system installed and connected to the system at the organisational headquarters. This allows the telephone network to be scaled and work independently, should the connection with the organisational headquarters be interrupted or lost.

Illustration - Branch Office Concept

Mobile devices used by employees (BYOD / CYOD) can be connected via the integrated GSM interface, enabling least cost routing, increasing employee mobility and transforming mobile devices into virtual extensions whilst employees are working from HomeOffice or are on the go.

Illustration - GSM Interface

Integration and Migration of Existing Telephony Appliances

Existing ISDN appliances can be directly connected to pascom. This allows for a gradual so-called soft migration where the immediate integration of existing end points and extensions is not required.

Illustration - PBX Soft Migration

Network Interface Configuration

Configuring network interfaces and adding VLAN interfaces using the web interface or TUI.

Applying changes to the network settings will result in the disconnecting of all active calls. Applying such changes using the TUI will result in a restart of the network without any additional warning.

Web UI Network Interface Configuration

The network can be configured using the Appliance > Network interfaces menu tool.

Screenshot - Web UI Network Interfaces

The list will show all available network cards, regardless of whether they have already been configured or not.

Changing a Network Interface Configuration

Select the network interface on which you wish to change the configurations (selecting multiple interfaces is also possible) and click the Edit button.

Mode Explanation
DHCP The IP address of this network interface is obtained via DHCP. The IP, Subnet and Gateway address fields can be left blank.
STATIC IP address, Subnet and Gateway addresses are manually assigned a static value.
DEACTIVATED Deactivates this interface.

Applying changes to the network settings configuration will result in all active calls being terminated.

Adding a Network Interface

Only virtual interfaces (VLANs) can be added manually. All available physical interfaces are listed automatically and do not need to be added.

To add a virtual interface, press the Add button.