First comment under 'Restrictions for DRE' -> DRE is a dual-side solution. Therefore, flow symmetry is required to configure DRE optimization. DRE isn't supported for asymmetric flows. https://www.cisco.com/c/en/us/td/docs/routers/sdwan/configuration/appqoe/ios-xe-17/appqoe- book-xe/m-integration-of-dre-with-cisco-sd-wan-tcp-optimization.html