The Heart and Brain of SDN
Pranav Arora · Advances in systems analysis, software engineering, and high performance computing book series · 2018
The chapter explores the various types and functionalities of controllers present in the field of software-defined networking. It is responsible for providing a bridge between various application interfaces. It enables smart networking and is solely responsible for having an authority over the network. It takes input from one API, processes it, and returns output for the high-level interface or API. They instruct the switch as to what functions to perform and can be of two types: either pure or hybrid. The controller at the central layer performs all the functions of the “evergreen” existing switches. The data plane of the router is solely the foreground for the switch to apply all its powers, while in hybrid switch software-defined networking and existing technologies work hand in hand. An administrator can build up the SDN tools to manage the traffic, whereas the existing network protocols progressively move the various incoming packets onto the network. This engenders hybrid network. Here the existing and SDN technologies or switches, work under the similar conditions.