Software Defined Networking
Software-defined networking (SDN) is an approach to computer networking that allows network administrators to manage network services through abstraction of lower level functionality. This is done by decoupling the system that makes decisions about where traffic is sent (the control plane) from the underlying systems that forwards traffic to the selected destination (the data plane). The inventors and vendors of these systems claim that this simplifies networking. SDN requires some method for the control plane to communicate with the data plane. One such mechanism, OpenFlow, is often misunderstood to be equivalent to SDN, but other mechanisms could also fit into the concept. The Open Networking Foundation was founded to promote SDN and OpenFlow as marketing using the term cloud computing became popular.
OpenStack is one of the cloud operating system that controls large pools of compute, storage, and networking resources throughout a datacenter, all managed through a dashboard that gives administrators control while empowering their users to provision resources through a web interface. It is an open source software. Below link provides further information on OpenStack.
RYU is a network operating system. It can be used to manage network and control apllications. Ryu is another component-based software defined networking framework which provides software components with well defined API that make it easy for developers to create new network management and control applications. Below link provides further information on OpenStack.
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