SD-WAN stands for Software-Defined Wide Area Network. It is a virtual WAN architecture that allows enterprises to leverage any combination of transport services, including MPLS, LTE, and broadband internet, to connect their networks over large geographical distances. SD-WAN uses software-defined networking (SDN) principles to manage and optimize the performance of wide-area networks by distributing network traffic across a WAN.

SD-WAN provides several benefits, including:

• Reduced costs: SD-WAN lowers WAN operational expenses, capital expenses, and overall total cost of ownership.
• Improved performance: SD-WAN assures consistent application performance and resiliency, automates traffic steering in an application-driven manner based on business intent, and improves network security.
• Increased agility: SD-WAN provides greater business agility and responsiveness to keep pace with IT innovations.
• Simplified WAN architecture: SD-WAN simplifies the management and operation of a WAN by decoupling the networking hardware from its control mechanism.

SD-WAN uses a centralized control function to steer traffic securely and intelligently across the WAN and directly to trusted SaaS and IaaS providers. It also allows companies to build higher-performance WANs using lower-cost and commercially available internet access, enabling businesses to partially or wholly replace more expensive private WAN connection technologies such as MPLS.

SD-WAN is a logical progression from the traditional WAN and its related technologies. It relies on virtual overlays that help teams change and replicate policies among distributed edge devices. SD-WAN enables real-time, automated, and standardized configuration changes, reducing the opportunity for human error that often occurs through the manual programming required by traditional WANs.

In summary, SD-WAN is a virtual WAN architecture that uses software-defined networking technology to manage and optimize the performance of wide-area networks. It provides several benefits, including reduced costs, improved performance, increased agility, and simplified WAN architecture.