TrustSec Inline Tagging is a Cisco SD-WAN feature that allows Security Group Tags (SGTs) to be propagated through the network along with the data packets. This ensures that the security policy based on the SGTs can be enforced across the network without requiring intermediate devices to have SGT enforcement capabilities. TrustSec Inline Tagging embeds the SGT information into the packet itself, allowing the network to maintain security group-based policies end-to-end.