Navigating the open source CMS selection process


The popularity of open source content management systems, and the number of open source CMS options have grown exponentially in the last three years. However, it has become increasingly difficult for users to separate the good from the bad, in a market where--irony of ironies--even proprietary options are trying to look more like open source projects in order to get buyers' attention.

Open source has become a buzz word for marketing material, said Kian Gould, CEO of open source consultancy AOE Media during a Dec. 2 session at content management conference Gilbane 2010, in Boston. "A lot of these so-called open core models don't have a contribution model. And that means, in the end, it's the same as proprietary software except you can look at the source code," said Gould.

It's not that open core is a bad business model for open source, explained Shaun Walker, co-founder and chief technology officer at open source content management vendor DotNetNuke. The licensing costs associated with a proprietary option are expensive, and still outweigh any implementation costs of open source, adds Gould. In his experience, open source implementation is usually 40 to 60 percent of the cost of a standing up a comparable proprietary solution.

Open source software licensing agreements can vary greatly and there are many licenses which are approved by the open source initiative. "In my opinion, though," said Walker, "most of these other licenses have only been created because, the creator, just wanted to add one other restriction to a more prevalent license. I would avoid those, and stick with the tried and true licenses that have been adopted readily by enterprises."

General Public License is the most common license, and is also referred to as a "copy left" license. The license helps ensure that intellectual property will always be available in the public domain. It ensures that open source remains open source, said Walker. Any derived work, based on the initial intellectual property, must be distributed (if the creator of the derivative work choses to distribute it) under the same license terms, meaning GPL software cannot be altered into a proprietary extension.

Permissive Open Source Licenses (BSD, MIT, MPL and Apache), (as the name suggests) have very few restrictions. The only real restriction for many projects under these licenses is that the copyright of the original creator of the intellectual property must be retained within the source code. If the original copyright is retained, it can be resold, distributed or modified.

Dual licensing and open core are not licensing models, but business models. Dual Licensing is when an original copyright holder of intellectual property licenses the exact same software under a commercial license and an open source license. The commercial license may have added benefits, such as support, while the open source license could be completely free--this model was pioneered by Red Hat, said Walker. Under an open core license, a central piece of software is licensed under open source license, but a vendor can build proprietary extensions, which are licensed under a commercial license and then bundled as a complete package. The open source core-commercial extension bundle is released for sale under a commercial license.

Forking is another term users should know prior to implementing a system. Forking is when there is an open source community that is not happy with the leadership, direction or evolution of the software. They can take an OS piece of software, and release it, make their own modifications and then release it under their name/branding with the retention of some of the original licensing. For example Joomla was a fork of the Mambo project, and now Joomla is much more popular they Mambo.

There is more to choosing a CMS than weeding through the licensing and business models. Next week FierceContentManagement will share more insight from Walker and Gould on picking the right open source solution.

For more:
- see the Open Source Initiative's information page on licensing
- see Shaun Walker's presentation (.ppt) from Gilbane 2010

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