What is Software-Defined Networking (SDN)?

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Software-defined networking (SDN) is a method of virtualizing networks with an intent to enhance their resources and speedily adjust networks to shifting business needs, traffic, and applications. It is done by bifurcating the control plane and the data plane of the network, which leads to the initiation of software-programmable setup that is very different from physical devices.

Since routers and switches, the conventional networking devices, are independent, they determine how to send its traffic. Each of these devices has two separate sections that work in tandem to send traffic through the network. They include a control plane, the mind of the device that determines where traffic should move to, and a data plane which takes the onus for forwarding data.

Many organizations, these days, are also unable to cope with the increasing adoption of cloud computing, the effect of the exponential growth of mobile phones, the surfeit of multimedia text and images, and unrelenting spending stress to cut down costs without affecting their revenues. All these combined are exerting pressures on conventional professional approaches on businesses. It creates problems in managing traffic flows over the network.

To not cave under pressure, most of them are embracing SDN technology to transform their network pattern and operations radically. Making use of open application programming interfaces (APIs), SDN facilitates the programming of network activities in a centrally regulated way via software applications. When operators open up usually closed network platforms and deploy a common SDN control layer, they can manage the complete network along with its devices steadily, notwithstanding the fundamental network technology’s complexity.

Following this, the automation of network management tasks can be improved. When unified SDN-control software can manage the network, it can lead to better network outlook and analytics because it gives them a comprehensive picture of the complete network infrastructure.

The major advantage of implementing SDN technology is that it lets software-based security tools to be seamlessly installed and managed better on server-to-server movement within a data center. Network administrators have more freedom to install virtual firewalls, network monitoring services, and encryption tools in an SDN environment to protect unfettered movement within the data center.


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Software-defined Wide Area Networking (SD-WAN), an extension of SDN, is the utilization of a software management platform to manage access to an enterprise’s branches. Earlier, users would operate with a single connection to their branches. SD-WAN has changed that by allowing enterprises to have multiple types of network connections in their branches, with a software management platform that is always available and can automatically rearrange traffic on a priority basis. With SD-WANs, users can save their capital expenses of not having to install a new customized WAN acceleration hardware by letting them run a software connection on a cheaper hardware device. According to IDC, a renowned global market research firm, SD-WAN market may rake in around $6 billion by 2020.

Lately, more and more deployments of SDN are being done to implement micro-segmentation, besides deploying software-based security products. It will allow users to branch a network connection between an office and an end user, with separate security settings on the different kinds of network traffic. For instance, a network could have a low-security network, which is public facing, without intruding into any classified information. While another division would allow restricted access control with a firewall that is software-based and having encryption policies in place, allowing confidential data to negotiate it. This is being done because even if malicious players access the public-facing network, they will be able to access the secure parts of the network.

If there are an increasing number of connected devices, there could be a logjam of network traffic. Advocates of SDN claim that a network-management overlay that is software based helps in carrying out analysis and prioritizing traffic better on the traffic category on the network.

Because of the advantages stated above, SDN is catching the attention of enterprises, software vendors, and resellers. Some of them believe that SDN will change the network landscape. At present, most companies that have deployed SDN technologies are data centers. But, with more successful adoptions happening now in enterprises, the rate of SDN deployments are picking up. Once software vendors can elucidate the nitty-gritties of SDN to software professionals, the rate of deployments will rise.

Most importantly, it should be conveyed that with SDN, networking environments become more flexible and vibrant.

Author Bio:

“My Self Sravani Mekala, I work as Staff Author at FieldEngineer.com a Marketplace for On-Demand telecom workforce, ranging from field engineers to high-level network engineers, project managers and Network Architects in 146 countries. I am a Computer Science engineer from JNTU. I can understand ongoing technology trends and keep myself updated in the technology industry.”

About the Author


Hi All, I'm Nicola and I am part of the EuroSTAR team. I enjoy outdoor activities and martial arts, it's fun! I joined EuroSTAR in 2018 and am excited to meet new people every year during the conferences. Tester Friends are for life :)
Find out more about @nicolag

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