3CX on Azure is the Cloud Ready for PBX?

 

3CX on Azure Maybe the Standalone Version

As an entrepreneur in the IT Industry I am always looking for new opportunities in IT. Is 3CX on Azure one of those opportunities? Our company, Austen Consultants is always on the hunt for new streams of revenue. It became apparent that VOIP is finally becoming affordable for everyone; the competitors like Cisco and the days of a 50,000 dollar investment to obtain an Enterprise IP PBX are over.

We first came across 3CX while doing research for a school district. A simple Google search for IP PBX and there it was…3CX. They were one of the first to come up in the search and within days we had a POC and shortly after, were signed up as a reseller and had our NFR Keys. I will go into more about this in another blog post. For now let’s talk about how and why we tested 3CX on Azure and vCloud Air.

3CX on Azure

Our company is a Microsoft Partner as well and use Microsoft Action Pack so we get $200 a month credits on Azure, perfect for a test bed for things such as a 3CX PBX in the cloud. After spinning up a 2012R2 VM and installing the standalone version of 3CX, we were able to start our testing. With a single instance, the results were positive, we could make calls and everything else appeared to be working on Azure. We connected Azure via VPN back to our Data Center in North Texas. We used an ASA 5505 and a few public IP addresses and via a Yealink T48G, we were making calls.

We tested Appia and Flowroute on Azure and we routed that voice traffic for SIP through the VPN connection. The VOIP carriers were connected on our Internet facing firewall and routed to Azure and our VM. Call quality was fine and for a company I think with enough bandwidth, a stable connection (we use Gigabit Ethernet from our provider) and a nice firewall I think the results would be a good or better than expected outcome.

If you are a company that wants to keep expenses down and pay as you go this might be a good fit for you. Since we are a hosted voice provider it doesn’t make sense for us to have a server for each customer. The prices for the bandwidth, server time and hard drive space would be to unpredictable leading to a huge bill from Microsoft.

Anyway, if you are interested in hosting a VOIP PBX it will not work on Azure using the 3CX Virtual PBX, here’s why. Using the 3CX virtual PBX requires that you have one server with up to 25 instances or customers. This server has one to one NAT with one public IP address. So here’s the catch, based on that previous statement each instance has it’s own unique port numbers, for instance.

• Customer 1 uses port 13060 for SIP and 13090 for the 3CX Windows phone tunnel
• Customer 2 uses port 12060 for SIP and 12090 for the 3CX Windows phone tunnel
• RTP Ports

Therefore connecting via ASA to Azure on a VPN listening for these ports does not traverse NAT well and it hates the VPN connection, also known as hair pinning. The audio suffers, the connection drops out and the configuration that would be needed is not worth the expense and effort. You can’t use Azure directly because you can’t open enough or forward ports through their firewall. So in my humble opinion Azure is out on the list as of now to use as a hosted platform for the 3CX Virtual PBX.

It made sense to us, as we would not have to invest in hardware and could use a pay as you go model and be up and running with little or no upfront costs. However, it’s just not there yet for a Hosted IP PBX provider like us. It is also not supported by 3CX. The standalone version is not as well as of this writing.

We ended up building out our own infrastructure at our data center using Cisco, Dell and vmWare as are hosting platform. This helps us figure our costs exactly with no guesswork and is a highly available platform to host our 3CX Virtual PBX. If you are interested in a hosted business phone system contact us and we would be happy to put you on our Hosted PBX our help you design and architect your own.