Table of Contents
Enterprises with more than one location have always needed some form of wide-area network (WAN). And now, enterprises of all sizes and shapes are becoming more and more distributed (even more locations). While this scenario has always been prevalent in specific industries, retail is one great example where it has quickly become the norm. At the same time, Software as a Service, Internet as a Service, Platform as a Service (SaaS, IaaS, PaaS), and various other forms of cloud services have become more widely adopted. This public cloud adoption often makes traditional solutions to corporate WANs, like managed, private, multiprotocol label switching (MPLS) networks, sub-optimal or even obsolete.
In addition to these fundamental shifts in the demands on WANs, the modern enterprise is more acutely aware of the need for security. It is more dependent than ever before on pervasive connectivity and network performance. This combination of trends has left IT managers scrambling for a secure method of reliably connecting their users, their data, and their applications. The software-defined wide area network (SD-WAN) has emerged to fill this growing need.
SD-WAN brings key tenets of software-defined networking (SDN) into the enterprise WAN, notably:
- Centralized control can be more efficient than distributed routing in certain scenarios
- Centralized management can make it much easier to operate a large network than traditional box-by-box management.
We can say that SD-WAN is a concept, not a technology, because there is not a single underlying protocol that defines an SD-WAN. Rather it is an operating model enabled by various vendors’ products in different ways.
While the SD-WAN market is not yet mature, many enterprises have already chosen to test or deploy SD-WAN solutions. The primary drivers include improved network performance, improved monitoring capabilities, improved security, and cost reduction.
When planning for SD-WAN deployment, multiple factors need to be considered. Many of these factors are directly related to the specific SD-WAN product you choose to deploy. Several others, such as which types of circuits to use for the physical connectivity and whether a do-it-yourself (DIY) or managed approach to deployment and operation is more appropriate, are typically independent of the SD-WAN technology provider you select.