An open book

InTech, Sep 2003 by Braun, David, Glenn, Nancy

Open source software has been such a growing trend over the past few years that it has turned into a buzzword within the information technology industry. In many cases, some confusion has grown as to what it means to say something is open source, and why such software exists.

There are several misconceptions about how to define open source software. Open source is often incorrectly lumped together with open application program interface (API) or open specification software.

Open source software has traditionally meant the uncompiled source code has gone to the general public with an acceptance of some license agreement. Some examples of these are GNU Public License (GPL), Berkeley Software Distribution (BSD), and Lesser GNU Public License (LGPL). These agreements allow you to download the software source code, compile it, modify it, and possibly sell it, as long as you provide a means to retrieve the original source code. Although in many people's minds open source means free, there are some companies now shipping the source code with their purchased products-open source does not mean just free software.

Open API means that sufficient documentation comes with a software package to allow a programmer to use it in other code he or she is writing. Open APIs are common with software libraries where you purchase code intended for use within your developed code.

An example of this is purchasing a collection of graphical interface beans (temperature and pressure gauges, dials and scales) to use in one or more applets that are the user interface to equipment controls. You may not have received the source code for the temperature gauge bean, but you get documentation on how to use the bean, and what interfaces and connections are available with this bean.

Open specification means there is a published document that describes how to build a piece of software. The most common example of a specification is standards development. Once the standard undergoes documentation, you can read it. An open specification is one that is freely available to anyone who wants a copy, without cost or membership requirements. A good example of an open specification is the World Batch Federation XML schema. The organization published the document with a license that allows anyone to read it and use it for development.

Why open source software?

There is no simple answer to why highly talented programmers develop open source software. Those who develop open source software for resale often express a belief in the goodness of sharing source code, as well as lowered costs for their development and an expanded development staff. It has become very common for companies to use the open source process for research and development, allowing the market pressures and interests of the global programming community to guide and power their new development activities without the overhead of hiring a development team. The motivations of programmers writing software they intend to give away for free are often unclear. The core motivations are being recognized as great programmers by their peers, seeing a need for a particular tool, "pizza ware" (getting free pizza), or the challenge of a new idea.

Whatever reasons these programmers have, we as users should support them. In many cases that is exactly what has happened. For example, Apache is a well-known web server that has surpassed many commercial servers in popularity. With this growth in popularity, some businesses are backing the Apache Software Foundation with resources to continue to develop, support, and maintain the software.

Companies that develop software under the open source model gain the benefit of having a mass of talented people working for them for the right to develop and tinker with the source code. A couple of examples of this are the Mozilla project sponsored by Netscape and Netbeans sponsored by Sun Microsystems.

Both of these companies use the open source implementation as the core of their supported product. The benefit to them is they acquire the innovation of new development within a common framework they based their product on. This reduces the cost of developing new features and increases the robustness of the software due to the number of people using the tool and developers fixing the bugs.

On the plant floor

When considering any software package or tool, there are three things to analyze:

1. Cost (initial and ongoing)

2. Integration issues

3. Flexibility and extensibility

Cost: The obvious cost savings when using open source software is in the initial cost and yearly maintenance. Open source software is significantly cheaper than its proprietary cousins, if not free. In the case where a vendor has used free open source software within their product, the cost of the off-the-shelf product may actually be lower for the bundled feature set. If the open source software you are considering is free, you can download it, compile it, and run it. You do not break any laws by doing this. This can be a real advantage if you are prototyping an idea for your information technology (IT) system and do not have significant development budget for capital software purchases.