Controller

Controller

Controller overview

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• Connect to the application (north direction), connect to the device (south direction), and extend left and right (east-west interface).
• Whoever controls the controller, or sets the standard, controls SDN.
• Southbound function: manage and control network devices through southbound interface technologies such as Openflow, such as topology discovery, table entry delivery, policy formulation, etc.
• Northbound function: There is no standardization, and it is relatively confusing at present. The main function is to be called by the upper layer.
• East-West function: maintain security (multiple controllers), realize election, collaboration, active/standby switchover among multiple controllers, etc.

Controller list

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controller name	leading manufacturer	Development language
OpenDaylight	Cisco	Java
Floodlight	Big Switch Networks	Java
RYU	Nippon NTT	Python
ONOS	ON.lab	Java
POX	Stanford	Python
NOX (first)	Nicira	Python