While many professionals from the telephone systems industry now indifferently use PBX and IP PBX to refer to the same thing, the latter is noticeably different, and appeared much later. Basically, these newer systems are PBX systems using the internet to channel voice calls as well as data within the company and between the company and the outside world. Let’s see how it both works similarly, and differently from a traditional PBX system, what features are supported, and what software can be used to operate this kind of phone systems.
How IP PBX systems work
IP PBX systems are nothing but PBX systems using the internet to channel data and phone calls.
Same as a PBX system...
Just like a PBX system, an IP PBX system will require the installation of a few hardware items:
- control board;
- PCI cards;
- Ethernet switch;
Lines are connected between each other, and with the “outside” phone system.
...using internet connections
IP PBX systems carry data using the TCP/IP connectivity, rather than the traditional phone line. In fact, the “IP” stands for “Internet Protocol”. Therefore, all the hardware mentioned earlier has to be TCP/IP compatible, like phones, gateways, cables... and the system connects to the outside network using the Internet Service provider and DSL or cable lines, rather than the public telephone system. Phones and other terminals are usually called “stations”, and lines “trunks”.
This has many advantages:
- Voice and data networks are blended into one single network, which means that all Voice-over-IP calls, POTS (“Plain Old Telephone Service”) calls and other operations requiring internet traffic like credit card payments or web surfing are using a single line to each user.
- This allows greater scalability as the business grows, while keeping costs down, especially with regards to international communications and maintenance costs.
IP PBX system features and software
IP PBX offers many features not available to users of traditional PBX systems. All these require the use of a basic, dedicated software to operate, and there’s not too many of them to choose from.
Even the most basic system will enjoy far more features than a normal PBX system thanks to the possibilities offered by the internet:
- VoIP communications: these phone calls are much cheaper, and these days even more stable than calls made using legacy POTS lines, and calls can be made using either a proper phone or a softphone;
- Mobility: the system can be accessed from anywhere with functions such as Find Me / Follow Me, remote IP extensions and fixed / mobile convergence.
- Voice messaging: now a common feature of all systems - visual voicemail or speech to text transcription are even possible;
- Video conferencing with high quality sound and image in real time communications;
- Advanced reposting features;
- Unified communications.
Examples of dedicated software
The essential basis of any IP PBX system is its operating software. There is a handful of PBX software available on the market, some of them open-source and free. Choices include:
- 3CX Phone System;