Compared to traditional software, using successful open source infrastructure components offers some key advantages:

Open source products typically not only have lower license costs, but also dramatically reduce the running costs that make up the total cost of ownership. An IDC1 study revealed that software cost is only 15% of the total cost of deploying an Oracle 8i Database application -- the hardware was 17%, staffing 21% and training 19%. A full 28% of the total cost of Oracle database deployment is attributed to system downtime. A comparable open source database reduces TCO by much as 90%. For large organizations, this can be savings on the level of tens of millions of dollars.

A huge community of users test open source software across a range of platforms before it is certified for production. Bugs are found and fixed quickly. Rapid iteration and extensive public review has helped make open source software more reliable than closed source.

As opposed to having hundreds of rarely used features, open source software focuses on the most essential capabilities. This makes deployment easier than proprietary software. Most mature open source software now comes with easy-to-use installation software, graphical management tools, and on-line help.

Open source software is typically available on dozens of platforms so you can choose the most economical combination of hardware and software for your needs. By providing ready access to source code, open source ensures freedom, thereby preventing lock-in to a single company or platform and ensuring access to your critical data in all situations.

Because open source software is out in the open, it is typically more secure and suffers fewer vulnerability attacks than proprietary software. When a problem is uncovered, it is addressed quickly.

source: A Guide to Developing an Enterprise Open Source Strategy, a MySQL Business White Paper, February 2005.