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Connecting Phone Systems

Branch Networking with VoIP

IP-telephony allows individual adjustments to the requirements of its users. One specialty of VoIP is the interconnection of multiple PBXs. With relatively simple means, two (or more) IP PBXs can be interconnected regardless of the geographical distance between them. This is a significant advantage over the traditional PBXs, which were expensive and complicated to connect over great distances. This has particular advantages for companies with more than one location.

Advantages of Branch Networking

Firstly, interconnecting phone systems will safe significant costs, as internal phone calls are completely free – even if the locations are on different continents. Phone calls via Internet make it possible for employees to exchange calls easily without adding cost to the company’s phone bill. Interconnection of phone systems does not just connect hard- and software, it connects people: staff moves closer together which in turn ensures a smooth flow of communication. If a colleague is unavailable, the BLF will signal his absence.

The function of “Remote Breakout” allows a caller from one location to use the connection to another PBX to call into that local landline. This is not just a further reduction of cost, the caller also appears to be local which can have a positive influence on the conversation. The connection makes call queues possible that can automatically forward a call, depending on location, time or language. A higher level of availability can be achieved, when calls are automatically transferred to the location that is open or available.

How does Interconnection Between IP PBXs Work?

The interconnection via Internet can be realized via VPN (Virtual Private Network). It is “virtual” in a sense that it is not a physical connection and “private” because it is self-contained. It serves as a passage way for an external party (like an employee in their home office) who wants to access an existing network (like the company’s local network). The same principle can be used for telecommunication, allowing the interconnection of two (or more) IP PBXs across unlimited geographical distance.

Is a VPN already in place, the connection of up to eight AskoziaPBX is incredibly easy. Through the IX Interconnection Add-On we ensure that the phone systems can communicate with each other. It is based on the IAX-Protocol which is used for Asterisk based PBXs worldwide. Just like the AskoziaPBX itself, the IX Interconnection Add-On stands out through its high usability, its flexible application and a friendly license model. There are multiple scenarios possible with IX.

Examples for Branch Networking Models

The first example shows three connected VoIP PBXs. Here, each PBX has their own internal phone number and each party has the possibility to call the parties of each of the three PBXs.

The second example shows two interconnected PBXs, where every system is configured as a separate network, having their own independent, internal numbers. Through dialing the configured dial patterns of one number, the party of the other PBX can be reached. Even calling from the local phone network of each of the systems is possible (Remote Breakout).

The third example shows three connected networks. Each with the same internal numbers for their parties. Through only dialing the internal numbers, one can directly reach the internal parties. If the dial patterns of an internal number are used, the parties from the other connected systems can be reached.

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