How does Cisco TrustSec classify traffic?

Cisco TrustSec classifies traffic using the Security Group Tag (SGT). The SGT is a 16-bit tag assigned to a user or device upon authentication, representing their security group. This tag is then carried with the traffic as it traverses the network, allowing network devices to enforce policies based on the SGT rather than relying solely on IP addresses. This provides a more granular and scalable approach to access control. The IP address and MAC address are traditional methods for identifying endpoints but are not used by TrustSec for classification itself; TrustSec policies are applied based on the SGT associated with that IP/MAC. While VLANs segment networks, they do not inherently provide the dynamic, identity-based classification that SGTs offer.