Software-defined networking in a wide area of network which is shortened as SD-WAN, is basically one of the products produced by the internet and computer which are recognized as the two most important technologies of all time, and its basic function is to simplify the operation and the management of a WAN or wide area network by decoupling or separating the mechanism of control of a network hardware. The designers and inventors of this certain product aims to help the business companies who wants to replace wholly or partially their expensive private wide area network connection technologies with a lower cost leased lines, and that is by allowing them to build a much higher performance of WAN. The business companies who are using such great technology can obtain the various benefits brought to them by such products and that includes the chances and privilege of connecting to remote branch offices to data centers and vice versa, delivering the applications and services that are required to perform the functions of these businesses and lastly, is the privilege of extending over a larger distance the computer networks that they have within their company. The products that are called as SD-WAN are designed by its manufacturers to address operational challenges or any other network problems that are existing, and some of the examples for these includes packet loss, service outage, network congestion, lower latency requirements of modern operations like video conferencing, streaming media, virtualized applications and desktops, and VoIP calling, bandwidth requirements for featuring high-definition video, difficulty and expensive costs of expanding WAN capability, difficulties in management of network and troubleshooting and jitter. When using the SD-WAN product it can now functions by replacing and enhancing the branch routers that are traditional by using virtual appliances, which main uses is to offer an overlay of the networks through the use of an inexpensive consumer level internet links which is designed to act as a dedicated circuit and controlling the application-level policies.
An SD-WAN product can be a physical appliance or a virtual appliance and they are commonly placed in small remote offices, branch offices, corporate data centers and cloud platforms. The various required characteristic of every SD-WAN products includes the ability to support VPNs or virtual private network and third party services like WAN optimization controllers, web gateways and firewalls, a simple interface that is very easy to manage and configure the ability of doing dynamic path selection which can be used for resiliency purposes or load sharing, the ability of supporting multiple connection types like frame relay, MPLS or multiprotocol label switching and higher speed LTE or long-term evolution wireless connections. The great common features that are being offered by the manufacturers to their probable clients and consumers includes flexible deployment options, and troubleshooting, simplified administration, includes QoS or quality of service, resilience, and security.