Voice communications using telephones has been a part of the business world for a long time now. Traditionally, businesses—especially large ones—set up their own internal phone systems, called private branch exchanges or PBXs. Traditional PBXs were, in a sense, a connection between the internal phone system operated by a company, and the phone service provider.
In the old PBX
setup, voice signal was delivered to the business by the provider, and from there it was handled internally by a switch the directed calls to the correct extensions. This type of system was hardware based (phone wire to internal lines to desktop phones) and generally so expensive that small businesses couldn’t afford anything beyond the most basic of telephony functions.
All of this has changed in the past few years, thanks to several developments. The introduction of the Internet led to innovations with Internet Protocol technologies resulting in the ability to send and receive phone calls over IP
networks—the same networks previously used mostly or only for data. When Session Initiation Protocol (News
) (SIP) came onto the scene, it became even easier to set up IP-based “sessions” for phone calls.
Finally, the increased availability of bandwidth needed to deliver high-quality application like voice has made the merging of Voice over IP and PBXs ready for primetime.
Today, even small businesses with limited budgets can afford a VoIP
century version of the traditional hardware PBX. This option is made even more affordable by the availability of hosted VoIP PBXs.
Here’s how hosted VoIP
PBXs work: the provider operates a fully redundant data center that hosts a “virtual PBX.” On the business (customer) side, IP phones are connected to the hosted VoIP PBX using an Internet connection. Instead of having to maintain phone system hardware on-site, the subscribes to the hosted VoIP PBX in the same way it does to an Internet service.
There are many advantages to the hosted VoIP PBX model. Perhaps most compelling is that the business does not need to maintain the system; upgrades, new features and troubleshooting are all handled by the provider. The phone system becomes an affordable, ongoing subscription rather than a bank-breaking capital expenditure and burdensome management expense.
Some functions, of course, are easier performed by the business than the provider. For example, if a new phone needs to be installed (plugged in) or permissions configured, IT staff can handle the task. That’s why most hosted VoIP PBX offerings include a Web-based administration panel for everyday moves, adds and changes (MACs).
Another advantage of the hosted VoIP PBX is that IP phones used can be unplugged, ported to some other location, plugged into another Internet connection (using a modem device), and be instantly up and running. The phone number and functions travel with the phone.
The diagram below shows two common connection methods for VoIP PBXs. On the top is the setup for a traditional (non-IP) phone, which uses an adapter so it can be plugged into the VoIP PBX. On the bottom is an IP phone plugged into a modem device. A desktop or laptop computer equipped with a headset and “softphone” software can also be used as a phone.
For small businesses, the invention of the VoIP PBX is a wonderful thing. It puts advanced telephony features in the hands of budget-constrained companies, helping them be more competitive. In many cases, a VoIP PBX makes the difference between being able to effectively remain in businesses serving a global customer base, or folding.