Evolution of Wide Area network from Circuit Switched to Digital Software defined Network

This era of digitization has seen the fastest growth of data and its applications. It’s rightly said that data is the new oil and the whole economy has started revolving around the data and communication. The over the top applications like WhatsApp and the content providers like Netflix and akamai are the examples of the new era unicorns. All this has led to immense pleasure on the transport or the Wide area network. This paper talks about the evolution of communication mediums, especially Wide area network transport from analog circuit switched systems to IP based digital transport and now software controlled wide area networks. The paper summarizes the concept of SDN and its applicability on Wide area networking. The concept of user and control plane separation is also evaluated and mapped with the advent of software defined networking. The paper also touches on the applicability of network function virtualization and its impact on the WAN transport. Security challenges and their mitigation methods are also talked about in the firewalling and VPN sections. Overall the business benefits which the technology has brought to the industry is being evaluated and described in detail. The paper also proposes a generic architecture of Software defined WAN with general purpose hardware and API based integration between various components.