There are a couple talks submitted on DefCore and Refstack, please help us out by voting and promoting them.
Interoperability: The Elephants in the Room & What We're Doing About Them: https://www.openstack.org/summit/austin-2016/vote-for-speakers/presentation/8645
Making Cloud Interoperability across OpenStack vendors a possibility using RefStack: https://www.openstack.org/summit/austin-2016/vote-for-speakers/presentation/7575
Let us know if you have submitted something else on DefCore or Refstack.
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