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How Open Source Spurs IP PBX Innovation

By Tristan Degenhardt


Being able to solve your own problems is an essential part of being an entrepreneur. It ranks right up there with being able to stretch a dollar, being in three places at once and constantly struggling to be the best at everything you do, as the top hallmarks of the entrepreneurial spirit. Its as if the open source model was tailor-made for just this type of individual, and when applied to a phone system, youve got a match made in heaven. An open source IP PBX allows even the smallest businesses to tap into features theyve never dreamed they could have in a phone system, while providing large enterprises with everything they need at what is usually a fraction of the cost of a proprietary system.

Open source is the term used to refer to software projects where the source code is made available by the author for the benefit of the users. Users or organizations who have the will and expertise can modify the code, and in so doing, customize the software for their particular use. The open source software philosophy has had a profound impact on the Internet, from the very low level, such as the Linux operating system, through the Apache Web servers that serve up an enormous share of the Web, to the Mozilla project and the Firefox Web browser. It is only natural, as IP technologies converge with telephony, that open source development should follow.

The open source IP PBX (define - news -alerts) brings the benefits associated with open source: stability, rapid development, flexibility, and cost savings, to a domain that has been dominated by proprietary technology controlled by large corporate entities. VoIP presents an enormous opportunity for businesses to save money, integrate data systems, and improve accessibility to its work force. By leveraging the collective development work, real-world deployment scenarios, and testing done by a large open source developer community, open source IP PBX systems emerge and mature more quickly than proprietary systems can.

A common misconception of open source software is that it is free of charge. The refrain most used to straighten out this notion is that open source is free as in speech, not free as in beer. By definition, software that is open source must have available source code, but that does not mean the product itself is free of charge. While many open source software packages are available at little or no cost, commercial packages of open source software are also available and are still considered open source. The most widely recognized example of this is the relationship of Red Hat and Linux. Red Hat sells and supports a particular targeted version of the Linux operating system. While Linux is free, Red Hats Linux products are commercially supported and tested, but still built on that free, open source software.

In the open source IP PBX domain, Asterisk is the most widely deployed solution and has incredible momentum. Digium is the corporate entity that provides the direction and management of the Asterisk project, keeping the development flowing and acting as a caretaker of the source code. The community that surrounds Asterisk can build upon the core IP PBX technology, adding features that allow them to build commercial Asterisk packages tailored for VoIP providers, SMBs, call centers, etc., while Digium supports those vendors and those vendors support their users. Digiums efforts are largely funded through sales of telephony interface cards, used in conjunction with Asterisk software to create hybrid TDM-VoIP PBX systems.

Pingtels SIPxchange, built on the software projects from the non-profit organization SIPfoundry, is another open source IP PBX solution available today.

Some of the key advantages of open source IP PBX are:

Cost Savings
Open source software is often associated with cost savings for those that choose to deploy it. This is particularly visible when comparing a free IP PBX to a proprietary system because of the high cost of those proprietary phone systems. Even when factoring in hardware, a commercial implementation of an open source IP PBX with support, and deployment costs, the price gap is often astonishingly wide when compared to a traditional phone system. This means that now even small businesses can afford an enterprise class phone system, and potentially save money by using VoIP services for their calls.

Given enough eyeballs, all bugs are shallow. Sometimes called Linuss Law, this was adapted from a quote by Linus Torvalds, the creator of the Linux operating system. It illustrates the fact that open source software often has a much larger testing base than conventional software and has the potential to be more stable that software developed by deep-pocketed proprietary juggernauts.

In addition to the wide base of users testing the software as its being developed, the free nature of open source software allows technically proficient users to actually fix the bugs that they find and that matter most to them, rather than waiting for a vendor to do it for them. This is particularly relevant in the telephony space where there exists a higher proportion of technical individuals in the user base for the software thats being developed. What percentage of users of Web browsers possess enough technical knowledge to actually write one? Hardly any. Compare that to IP PBX users and that percentage is significantly higher, leading to rapid and stable development of the most important features.

Interoperability and Rapid Development
In addition to improved stability, the open source development method also presents a great benefit to interoperability, something especially important as VoIP technology matures. Open source platforms such as Asterisk have users in hundreds of countries, connecting it to every variety of hardware imaginable. A programmer in Norway can add support for Norwegian busy tones, and test its compatibility with the Norwegian PSTN. Multiply this type of targeted development across a multitude of international users, and it becomes apparent how an open source platform can quickly achieve a task that would be prohibitively expensive for a commercial entity to accomplish.

This process also works for interoperability with equipment from other manufacturers. Often, the manufacturers of VoIP devices such as SIP handsets will donate development time to ensure that their products interoperate with open-source software. This allows VoIP offerings based on open source projects to interoperate with a wide array of devices, giving consumers more choice.

Commercial Business Models & Open Source
A common analogy about commercial open source business models takes the beer out on the town: The recipe to make beer is readily available for free on the Web, a premium beer at a bar will cost you about five bucks, and a cab ride home runs about twenty dollars. Your free beer recipe is your freely available open source code. The premium draft represents the companies selling pre-packaged open-source software (and perhaps services if theres also a band playing and youve tipped your bartender). The cab ride home represents the service industry that has grown up around supporting open source software and is where a lot of the revenue is to be made with open source. Despite the recipe being freely available, people everywhere still head out for beer and businesses thrive.

There are many examples of this ecosystem at work in the open source telephony space. Digium, the corporate sponsor of Asterisk sells telephony cards, along with a commercial version of their software called Asterisk Business Edition. Pingtel sells a commercially supported version of their open source PBX platform, SIPxchange. On the purely service side of the spectrum, companies like Sokol Associates provide Asterisk training and organize the AstriCon Asterisk convention.

The emergence of the open source IP PBX into the market is a good sign for consumers of phone systems. Analysts have been trumpeting the incredible growth predicted for IP and hybrid PBXs, while witnessing a decline in TDM systems. Look for upstart startups to shake up this space as adoption of Linux and Firefox have made Microsoft sit up and take notice. The next round of truly innovative IP PBX applications will come not from the names youd expect, but from the small companies gaining momentum now, when the IP PBX market is beginning its rise to the top. As more users adopt VoIP for their homes with services like Skype and Vonage, they will bring their experience into the workplace and be looking for inexpensive, business-class VoIP solutions and open source IP PBXs certainly fit the bill. IT

Tristan Degenhardt is vice president of operations at Switchvox. For more information, please visit the company online (news - alerts).

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