How Does SD-WAN Work?
Traditional WANs rely on physical routers to connect remote or branch users to applications hosted on data centers. Each router has a [data plane], which holds the information, and a
[control plane], which tells the data where to go. Where data flows is typically determined by a network engineer or administrator who writes rules and policies, often manually, for each router on the network - a process that can be time-consuming and prone to errors.
SD-WAN separates the control and management processes from the underlying networking hardware, making them available as software that can be easily configured and deployed. A centralized control pane means network administrators can write new rules and policies, and then configure and deploy them across an entire network at once.
https://docs.paloaltonetworks.com/sd-wan/3-0/sd-wan-admin/sd-wan-overview/about-sd-wan

https://docs.paloaltonetworks.com/panorama/10-2/panorama-admin/panorama- overview/panorama-models