Choosing the right IP telephony service (PBX, Centrex)

October 2016

Over the years VoIP technology has become quite popular in the business world. This article will help you to choose the right VoIP service.

Analyze the existing system

This is the first point to consider, when migrating to an IP telephony service. The packages from internet service providers may be sufficient for some small businesses, which do not have specific needs related to telephony. Some business already have an analog telephone system, in this case a migration to a PBX or Centrex system may be the right choice. In all cases, the analysis of the existing system is not to be overlooked.

Define the scope of your project

You need to take into account the needs of the business in terms of telephony services, to fully optimize your system. If you only have one line in your business, you can opt for the VoIP packages offered by your ISPs. However, if you have multiple lines in the business and a telephone system, then it is better to make use of a PBX or Centrex system.


If you already have a PBX system in the company, the principle is the same: the IPBX can connect the internal lines and initiate external calls. IPBX also support conference calls, call forwarding etc.. The system may be deployed in the company directly, without going through remote servers. IPBX system starts at 40 €/HT per line, for unlimited calls on land line and mobile numbers (depending on the ISP).


The features are exactly the same as on a IPBX system, however, the Centrex allows you to host the system on remote servers (the ISP server for example). This type of of system allows you to outsource network administration and reduce maintenance costs. Centrex is particularly well suited for businesses with many telephones lines.
Centrex system may cost around 15 €/month per line.

Choosing your operator

The number of operators offering VoIP solutions has flourished in recent years! You can select an operator to match the specifications of your business! In general, consider the different options carefully: some operators offer unlimited offers (international or mobile phones).

You must be careful about the levels of guarantee offered by operators: some operators provide a 24h/24h maintenance service.

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