Software Defined Networks
Software defined networking is a new concept that redefined the current network device architecture and the way they behave. Due to the exponential growth of the Internet and services attached to this worldwide infrastructure, a number of issues have cropped up in modern day networks. This paper discusses a few of these limitations and how the software defined networking approach tries to alleviate them. OpenFlow, released in the year 2008, is a commercially viable implementation of this concept that is being well received by the networking industry at large. The paper also discusses the OpenFlow protocol, its implementation and the challenges facing its widespread acceptance
1. Introduction …show more content…
In a traditional network, the network traffic is controlled by controlling the dataflow in individual switches and routers. The typical dataflow in a switch includes:
Data plane: Includes the physical components that are used to carry the packets from one port to another using the logic embedded in the hardware.
Control plane: Includes the logic that is used to program the data plane.
Management plane: Used by network administrators to manage the control plane. Figure 1: Conceptual Diagram of Traditional Switch 
The issue with this traditional approach is that, since each device has its own control and management planes, they have to be configured individually. This also led to limited visibility of the overall network performance as each device could account for only its own parameters. Figure 2: Architecture of Software Defined Networks 
SDN tries to abstract the control plane of several network devices into a remote controller thereby being able to control and manage then from a single point. This single control works at a level of abstraction that corresponds to the entire network itself, and the devices are relegated to just the dedicated switching hardware. With single virtualized control plane, the administrator can configure network parameters such as bandwidth, latency, security and other QoS parameters for the entire network from the remote