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OpenDaylight Introduces Nitrogen

By Blog

I am very pleased to announce the seventh OpenDaylight release, Nitrogen. We’ve done something a little bit different with this release.  First, we wanted to shorten the development time for this release so that we can better synchronize our future releases with OPNFV, Open Stack, and ONAP.  To that end Nitrogen arrives just over 3 months after Carbon.  Second, given this reduced development schedule, we’ve focused our efforts on a small number of key features requested by our users.

The primary focus for Nitrogen is the implementation of Karaf 4; the OpenDaylight component that allows the user to pick and choose what protocols and services their SDN controller will support.  With this update, OpenDaylight significantly improves the management of interdependencies between its component packages. This has three benefits from a user standpoint:

  • Overall platform performance. Because Karaf 4 generates and maintains a map of dependencies, both startup and new feature deployment can be much quicker, depending on your configuration.
  • ODL depends on 3rd party features that interact with parts of Karaf, but until the Nitrogen release, they were not covered by the Karaf security features.
  • The same dependency map that speeds deployments also makes it easier to track, isolate and discover breakdowns and errors.

Another benefit of moving to Karaf 4  is that it simplifies the integration of new features.  It does this by requiring the declaration of all feature interdependencies, as well as all the bundles a given feature contains, as part of the packaging process. Previously, ODL modules didn’t always require this information at startup, and instead the dependencies would be resolved on the fly.  From experience, the Karaf project and OpenDaylight recognized that this method was not 100% foolproof.  Therefore, the Nitrogen release cycle focused on making significant improvements in explicitly declaring these dependencies as part of the exercise of migrating our modules to Karaf 4.  The end results give developers and users a platform where all interactions between modules are explicitly defined and consistently executed. ODL Community member Ryan Goulding provides further details in this blog.

In addition to Karaf 4, significant effort has gone into improving the scalability, and robustness of OpenDaylight’s clustering capabilities.  Performance testing run in parallel with development surfaced feedback and new ideas that enhanced the Nitrogen release as well. Finally, small enhancements and bug fixes have been applied across the spectrum of components that make up OpenDaylight.

With these foundational improvements in place, OpenDaylight is well positioned to charge ahead with the Oxygen release, which will follow the traditional six-month cycle.

What’s next for OpenDaylight? We’ll continue to build capabilities to support active and emerging use cases in mobile carriers, webscale enterprises, cable operators, and IoT consumers from healthcare to utilities. The Design Forum for Oxygen is coming up on October 9-10 in Santa Clara, CA—join us to help define OpenDaylight’s next release.