Software Defined networking in Wide Area Network is otherwise called as SD-WAN. SD-WAN is used to simplify both the management and the operation of WAN by means of decoupling or separating networking hardware from the control mechanism. This idea is almost similar to the way how software defined networking is implementing virtualization technology in order to improve operation as well as data center management.
The key application for SD-WAN is to allow companies develop higher performance wide area networks by utilizing commercially available as well as low cost internet access. As a matter of fact, this has made it possible for business owners to have an alternative in replacing expensive private WAN connection technology be it partial or whole.
Through the use of WANs, it makes it possible for the company to connect distant branches into their data center and to each other, extend the reach of their network and also, deliver a better application and service needed by the business. When companies extend their network to cover broader distances and across multiple networks too, they face various operational challenges. This includes but not limited to network congestion, packet loss, jitter and occasional service outages.
Be it VOIP calling, streaming media, video conferencing and virtualized desktops etc. all these new innovations call for low latency. The bandwidth requirements are increasing too especially for apps that feature HD vides. It can be difficult and expensive at the same time to expand the capability of WAN. SD-WAN products are made mainly for addressing these network problems. Through replacement and enhancement of the conventional branch routers by taking advantage of virtualization application controlling the app level policies while offering network overlay as well, consume grade internet which is less costly can now act as a dedicated circuit.
As a matter of fact, this is simplifying the setup process for the branch personnel. SD-WAN products might be virtual or physical appliances and installed in corporate data centers, bigger offices, remote offices and so forth.
Centralized controller is being used for prioritizing traffic and setting policies. In terms of redirecting traffic, that would not be a problem either as SD-WAN takes into account the availability of network bandwidth and policies. Basically, this helps in guaranteeing that the performance of application always meets the SLA or Service Level Agreements.
Several research studies has concluded that for SD-WAN to be efficient and effective, there are 4 things that it should have and these are about providing simple and easy to use interface, support VPNs, do dynamic path selection for load sharing as well as resiliency purposes and lastly, support multiple connections.