How it Works
SDN is a paradigm that provides for separation between the control and the data planes.
SDN control plane components communicate with physical layer infrastructures and abstract
the network resources into virtual resources through a standardized interface that can hide
hardware-specific implementation. Based on the resource state and application demand, optimized
decisions on how a flow (or a connection) needs to be set up across the network can be reached by the SDN
operating system, and then physical layer resources will be configured via a network control protocol, such as
Openflow. Orchestration platforms can provide interconnections and orchestrations between SDN-enabled networks
and non-SDN-enabled networks, making them coexist to serve an extensive range of applications. Applications can
interact with the network dynamically using an application programming interface (API) to allow for better
orchestration of network resources, optimize overall network performance, and provide for the application
needs.
SDN for Optical Networks
SDN implementations for optical networks are more complex since they must account for physical layer
constraints including optical signal reachability, bandwidth availability and granularity, physical layer
impairments, light path routing, and lightpath reconfiguration speed. CIAN is working on the software-defined
optical networks with full physical layer controls, enabling physical layer programmability through open control
systems.
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