How to Deliver Asterisk as a Service

The traditional hardware-based phone system is dead! Well, maybe that’s an overstatement, but the rise of open-source software-based PBXs is shaking things up. One of the major advantages of an open-source PBX system is you can deliver it to the client as a service. With the code provided by the open source model, you have the ability to create custom solutions for your clients’ needs as well as avoid the high cost of licensing typical with traditional PBS systems. You immediately get the attention of an SMB client when they learn the features of a $30,000 PBX can be delivered as a service with very little money upfront.

As an example, my company offers a bundled local, long-distance and PBX service. The PBX is still located on premise, but we charge for it on a monthly basis along with the network services. We add a 100 percent hardware warranty and service on the PBX server for the life of the contract. Software upgrades and any PBX troubleshooting are included. We also include 24x7 monitoring of the carrier router, client firewall, PRI circuit and phone server.

To go to market with such an offer, one of the first decisions you¬¬ need to make is whether to provide your own support or purchase a vendor-supported product. We chose to go in-house using freely available open-source products, because we have been running Linux-based systems for many years and have a very strong in-house support staff. However, turnkey systems, such as Switchvox from Digium Inc., Trixbox from Fonality Inc. and several others exist if you’re not comfortable with supporting the systems under the hood.

Many open-source options also are available for the core engine for your PBX. Our choice was to go with one of the most active development projects around, Asterisk by Digium. New features constantly are being developed for the Asterisk platform, and there is a large community from which to derive support.

Standardizing on your configuration is another key element in successfully delivering a stable platform to your clients. We typically start with a PRI circuit from the carrier, which is connected to a Digium T1/PRI card in the back of our server. In addition, we standardized on IBM as our server vendor because its gear is engineered for the enterprise and is supported by a wealth of published technical information. We also selected one model from within the IBM product line as our core solution. This has greatly reduced our troubleshooting when problems arise.

Next, you need to procure your PBX server platform. We recommend sourcing from reputable companies that specialize in off-lease hardware. Since the servers typically have been running in a data center for the duration of the lease, you can be confident they are in good working order and have been well maintained. The costs will be far less than purchasing new hardware and depending on the server manufacturer, you may still be able to obtain warranty support. Additionally you will have the opportunity to purchase spare units should a production box suffer a failure. You can find off-lease systems by searching the Internet. What are you looking for? A typical server for a 25- to 50-user environment, for example, requires a dual PIII with 2-4GB of RAM and 18–26GB of hard drive space.

Now that you have your server hardware, you need to load the operating system and PBX software. We chose CentOS, the community enterprise operating system, based on its stability and support. The PBX software is comprised of Asterisk core with FreePBX and Trixbox Web interfaces. Asterisk supplies the core functions and FreePBX and Trixbox provide the GUI and feature sets that make the system easy to administer.