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Leveraging dynamic deployment and scale frameworks present some challenges to the ONOS controller. This is because in an OpenFlow environment the assumption is that the device is configured with the IP address of one or more controller which it will contact to receive control plane instructions, yet in these dynamic deployment environment the IP addresses of the individual components (i.e. ONOS controller instances) are essentially obfascated obfuscated and not meant to be exposed or really important as any individual instance should be able to disappear or reappear at will. 

ONOS Clustering

One of the obstacles

• mastership (write authority for device)
• sticky balancing
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