Traditional network management has been replaced by a method known as software-defined networking (SDN), which makes it possible to dynamically and programmatically configure networks in order to improve network performance and monitoring.
Components of an SDN architecture are as follows:
Many years have passed since the advent of software that could determine the best routes for data transmission or configure individual networking devices. To date, however, most of the tools have been vendor-specific and restricted to the networking ecosystem. SDN has a good components in its architecture that make things better, including centralized control, programmatic interfaces, and integration with orchestration/automation tools[1,2]. Figure 1 shows the architecture of SDN.
- SDN Controller Plane: The northbound interface of the SDN application communicates network resources and network devices to the SDN controller (NBI).
- SDN Application Plane: Controls the SDN dataplane by acting as a translator between the SDN application layer and the dataplane themselves. As well as providing an overview of the networks and traffic for SDN applications, it acts as a central repository for network policies.
- SDN DataPlane— Switches that move data packets on a network are implemented in SDN DataPlane
It is possible to communicate between the SDN Controller and the network’s routers using APIs, whether they are open or proprietary.
The Process of Software Defined Networks:
Centralized SDN controllers are used to deliver software-based network services in an SDN environment. It is possible for a network administrator to manage network policies from a central control plane without having to deal with individual switches.
The three layers of SDN architecture communicate with each other via northbound and southbound APIs (APIs). A northbound interface can be used to communicate with the controller. The controller and switches can communicate with each other via the southbound interfaces.
Among the layers are:
SDN applications communicate with the SDN controller via the application layer, which is where they exchange behaviours and resources they require.
Manages policies and traffic flow in the control layer The data plane’s behaviour is controlled by a centralised controller.
Infrastructural layer — Comprised of the network’s actual switches.
Software Defined Networking (SDN) has the following advantages:
Switch rules can be changed on the fly by network administrators, giving them greater control over traffic flow. In cloud computing, multi-tenant architecture is essential because of this flexibility [4-7].
It is not necessary to set up individual devices when policies are distributed through a centralised controller.
In order to identify suspicious traffic and reroute packets, the central controller must be able to see the network traffic.
Virtualization of services reduces the need for expensive hardware, making it more efficient.
 Bhushan, K., et al. (2019). Distributed denial of service (DDoS) attack mitigation in software defined network (SDN)-based cloud computing environment. Journal of Ambient Intelligence and Humanized Computing, 10(5), 1985-1997.
 Mishra, A., Gupta, N., et al. (2021). Defense mechanisms against DDoS attack based on entropy in SDN-cloud using POX controller. Telecommunication systems, 77(1), 47-62.
 Scott-Hayward, S., O’Callaghan, G., & Sezer, S. (2013, November). SDN security: A survey. In 2013 IEEE SDN For Future Networks and Services (SDN4FNS) (pp. 1-7). IEEE.
 Ahammad, I., Khan, M. A. R., Salehin, Z. U., Uddin, M., & Soheli, S. J. (2021). Improvement of QOS in an IoT ecosystem by integrating fog computing and SDN. International Journal of Cloud Applications and Computing (IJCAC), 11(2), 48-66.
 Bhushan, K., et al. (2018, February). Detecting DDoS attack using software defined network (SDN) in cloud computing environment. In 2018 5th international conference on signal processing and integrated networks (SPIN) (pp. 872-877). IEEE.
 Prathiba, S. B., Raja, G., et al. (2021). SDN-assisted safety message dissemination framework for vehicular critical energy infrastructure. IEEE Transactions on Industrial Informatics.
 Mishra, A., et al. (2021, January). Entropy based defensive mechanism against DDoS attack in SDN-Cloud enabled online social networks. In 2021 IEEE International Conference on Consumer Electronics (ICCE) (pp. 1-6). IEEE.
- How SDN is different from Traditional Networks
As per the operational and management view , SDN can smooth the operational processes, and reduce the manual errors. Also forward traffic in an unconventional ways.
2. Is OpenFlow set to take over as the primary method of distributing traffic in a network?
At this point, OpenFlow’s long-term future is unknown. Soft switches that run in a hypervisor, relying on server-based x86 computing power to perform the necessary processing, have proven to be the most effective use of OpenFlow, according to some.