OpenStack and Cloudscale are better choices for complex applications than Eucalyptus, says Nataraj, because they do a better job of hiding the complexity of networking. For an application that, for example, requires a user "to connect from a different IP range," a customer would "have to write custom code to make that happen with Eucalyptus," he says. With OpenStack, the "switches" required to make those new network connections are already present.
The number and quality of developers involved in an open-source project can also be a good indication of the project's quality, many observers say. If developers from several companies are involved, vendor lock-in is less likely to be a problem, says Nataraj.
Roby, however, suggests focusing on a commercial vendor's level of commitment, rather than that of the community. "It's largely a myth that there's a lot of new code being developed by a large group of people," he says. "Any of these successful products are developed by a small group of people," with the community at large "providing feedback and maybe doing testing or providing documentation."
Miles also warns of "token" open-source efforts by partnerships among major vendors. "If both those companies don't really rely on the product for revenue, at any point in time either or both will just walk away, and the product will die," he warns.
The unconventional licensing terms that some open-source developers impose on their software, such as one requiring that "the Software shall be used for Good, not Evil," raise eyebrows in corporate legal departments. Posing a more serious problem are licenses that require a company to share any enhancements with other members of the community -- which creates the possibility that the company may have to reveal "best practices" to competitors.
Most experts interviewed say mainstream licenses such as Apache's don't impose such troublesome requirements. In any case, says Conway, his staff's processes and skills are just as important as any code he shares with others. And, he points out, open source also lets him use improvements made by others.
Open-source cloud frameworks have the potential to make it far easier for organizations to meet changing business needs by quickly deploying Web applications across public and private clouds. But to get those benefits, IT architects must sift through the various meanings that different vendors have for their "frameworks" and whether each framework can deliver the level of ease of use they need to meet their specific requirements.
Scheier is a veteran technology writer. He can be reached at firstname.lastname@example.org.
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