A Software Defined Wide-Area Network (SD-WAN) applies Software-defined Networking to Wide Area Networks (WAN). It uses abstracted architecture in order to remotely manage and construct the network. Individually managing each hardware component of the network is no longer needed, saving significant time and operation costs in managing large distributed networks.
What is the history of SD-WAN?
The transition to SD-WAN began in the 1980’s with point-to-point (PPP) lines, and grew in the late 90’s and early 2000’s with the emergence of Frame Relay circuits, as new technological developments emerged. SD-WAN emerged on the scene in 2013. Many modern organizations are still retrofitting legacy architecture and infrastructure with SD-WAN technologies. Why? It provides organizations with a wide variety of advantages. ,
What are the advantages to using SD-WAN?
Regular WAN can prove restrictive in that organizations have to connect to the Internet and cloud applications via legacy MPLS links to the data center and then to the internet and cloud. By using direct internet connections from the remote office over available broadband, cellular and other direct Internet links, SD-WAN offers cost savings and more reliable connections when it comes to utilizing the cloud.
In addition, SD-WAN can:
- Improve visibility into applications
- Reduce latency
- Reduce packet loss
- Improve throughput using technology
- Centralize management across branch networks
- Make traffic management elastic
- Minimize branch networking capex and opex
- Reduce vendor lock-in
Organizations can deploy SD-WAN themselves, or they can opt to work with a managed service provider. This provides organizations with flexibility, and allows for a high-level of customization.
What about security when it comes to SD-WAN?
Moving cloud connections from the data center to direct connections to the Internet managed by SD-WAN distributes security to a branch level, meaning that data does not need to be routed through a data center in order to receive security protections. This shifts where security is applied to the connections. Security can be applied on the branch SD-WAN device or via a cloud security service or Firewall-as-a-Service as in the Gartner SASE model. With a SASE model, it’s possible to apply the same level of security as that applied in the data center when using legacy WAN technology. In addition, SD-WAN inherently segments your network and shifts to applying security to each session as needed, minimizing potential attack damage.
Options for different types of policy settings can help organizations avoid malware and can provide access control.
Typically, SD-WAN solutions include robust analytics dashboards that enable you to survey your entire system. You’ll be able to easily gather information on applications, user views and network topology.
What type of SD-WAN security solution should you look for?
- Invest in an SD-WAN security solution that includes a next-generation firewall with unified threat management.
- A unified security architecture can help you reduce OpEx costs by as much as 40%, and CapEx by as much as 20%. 
- Get an SD-WAN solution that’s dynamic, flexible and efficient.
 CATO Institute, “SD-WAN Explained”
 CATO Institute, “A History of SD-WAN”
 Check Point Software, “Branch Cloud Security: Securely Connect your Branch to the Cloud”