“…In [13], a software-defined networking (SDN) 64 [13] control platform is developed, which is based on the Open-65 Daylight (ODL) controller [15] but with some key functional 66 modules (e.g., Forwarding Rules Manager) extended to support 67 the control of optical network devices. OpenFlow (OF) [13] 68 agents are built for the non-OpenFlow enabled devices, while 69 the OpenFlow protocol is extended to enable communication 70 between the SDN controller and DCN devices. This SDN con-71 trol platform enables on-demand, flexible, and programmable 72 optical DCN connectivity services [13].…”