I admit I have a dog in this fight, but today I would like to discuss PBX systems, and in particular 3CX.  I want to start out real basic, and talk about some terms.


PBX stands for Private Branch Exchange.  A PBX is exactly what it sounds like, a private phone network, typically used in businesses.


VoIP stands for Voice over Internet Protocol (IP), and is the protocol used to allow digital voice communication over the internet.  Instead of a traditional phone company scenario, where they run a dedicated phone line to your location and then you use the phone company network; you use the internet for VoIP.


A DID (Direct Inward Dialing) is a service provided by phone companies, or local exchanges which provide blocks of numbers.  The DID is a phone number, but for the digital world.  Think of it very similar to purchasing a domain name, except this is a phone number.  Once you purchase the number, you point it at your phone system, much like traditional web browsing technology now.

Advantages to VoIP and PBX

Unlike traditional phone systems, which require a phone line for each extension coming in from the phone company, a PBX can break a single line into several extensions.  This allows for reduced overhead costs, since the business can take advantage of a single phone line (or several if needed) in the form of a DID.  The overhead of a DID is typically much lower than dedicated phone services from a phone provider.  

Typically, a DID can be purchased for maybe a dollar or two USD per month, then you get billed on usage.  There are many other options, including calling plans very similar to full service phone companies offerings, but you start getting into more expensive options over a prepackaged solution.  In this regard, I can only suggest you do your research when looking for a SIP trunk provider.

PBX Options

There are several big names out there which provide PBX solutions.  Some provide the PBX solutions at a cost that makes you wonder how anyone sleeps at night.  Think proprietary hardware, proprietary phones, proprietary software, mandated support (trust me, you'll need it), and a perpetual license which make zero sense to anyone besides the bank.

3CX is used by major brands all over the world

Another option would be 3CX, which is also a full service PBX solution.  For starters, 3CX does something a bit differently when it comes to their licenses.  A little bit of research would find that most PBX solutions typically charge based on extensions.  This makes sense for small businesses, which have a finite use case, and may only need one or two extensions total.

What about the bigger companies, and I'm not talking IBM or Apple here, I mean 10 employees.  What about the small, no, tiny businesses?  They are everywhere, and honestly get raked over the coals daily by the phone company.  What if they had a better option, without having to spend thousands to get into the solution; or thousands to keep the solution?  3CX is providing enterprise options at standard licensing reach.  By default, 3CX allows unlimited extensions in every license offering.  Each license can support over 1000 Simultaneous Calls, but this is where the license gets more expensive.

License based on Calls

Instead of charging for extensions, and limiting the use of the PBX due to cost, 3CX decided to charge based on actual call use.  Based off Simultaneous Calls, the license allows for a certain number of calls to complete before reaching the license limit

For example:

Pretend you have a company with 20 people.  Each person has an extension, and two phones associated with the extension (one softphone, one deskphone), and each person is in the office for several hours each day.  You need to look at how many simultaneous calls you expect to have at any given time, including internal calls.

If this were a call center, the likelihood of a person getting a call (often) is high.  In this case, you may want each person to be able to accept 2 - 3 calls in a call queue, and would need to take 30 - 40 simultaneous calls to make this call flow work.

The inverse is also true if this were a small consulting company, where the likelihood of a person getting a call is more seldom.  You may not have call queues, or queues that remain empty, and can reduce your simultaneous calls significantly.  In a low volume scenario such as this, you may only need 10 simultaneous calls, as your chances of using more than this at any given time is extremely low.  

Again, it all comes down to the actual use case.  In several use cases, you can have a high volume of calls and still maintain a low phone bill.  The advantage is with the liberal license provided by 3CX.

Need more?

What are you waiting for?  3CX has everything you need to get your phone system off the ground with minimal cost to start (free 3CX license for a year), works with existing (read: not proprietary) phones that you and I can buy off any sane online retailer or box store.  Reach out for more information on PBX Systems, including getting a free demonstration.

3CX Basic Certified Engineer Blaine Bouvier