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SD-WAN virtual networks installed over a conventional WAN infrastructure can increase the agility and flexibility of companies using cloud-based applications.

The WAN – which stands for Wide Area Network – is a conventional company IT network, made up of machines, servers and physical circuits, that tends to lack the flexibility required when the company decides to extend it to cover external sites or far-flung subsidiaries. But upgrading it to meet a company’s growing connectivity, mobility, and data access needs can prove complex and costly.

A new technology, SD-WAN (Software Defined Wide Area Network) has come on stream at the right time to meet these flexibility and acceleration needs, and companies have been quick to embrace it. Gartner Consulting predicts that by the end of 2019, nearly one in three companies will have rolled out the virtual network over its physical network.

Cloud first

SD-WAN is a software overlay technology, says Chris Gilmour, Technical Practice Lead at Axians UK (VINCI Energies). It operates independently from the physical network and enables applications to be accessed by remote sites using underlying infrastructures as diverse as generic Internet connectivity, 4G/5G, and MPLS via a secure tunnel without using a gateway. “Disconnecting the application traffic from the underlying infrastructure generates substantial flexibility,” he says. He defines SD-WAN as a “transformation accelerator that creates an application-centric “cloud first” model.

SD-WAN is “a transformation accelerator that creates a ‘cloud first’ model”

SD-WAN’s ability to combine several connectivity technologies supports a good level of bandwidth management. This in turn enables the network to handle applications differently according to pre-defined criteria.

“In addition,” says Chris Gilmour, “this technology provides extensive application visibility, granular reporting, and better network management.” Lastly, even though this is not the main reason companies install an SD-WAN network, the Axians UK Technical Practice Lead points out that “Data management and storage can also be made more flexible and more agile,” since it constitutes one of the network’s applications.