Cisco TrustSec, also known as CTS, is a security architecture that enables secure networks by establishing domains of trusted network devices. The main components of Cisco TrustSec include: * Authenticated networking infrastructure: This involves the authentication of devices within the TrustSec domain. The first device, known as the seed device, authenticates with the authentication server, and subsequent devices are authenticated by their peers within the domain. * Security group-based access control: Access policies within the TrustSec domain are based on the roles of source and destination devices, indicated by security group numbers, rather than network addresses. * Secure communication: Communication between devices in the domain can be secured with encryption, message integrity checks, and data-path replay protection mechanisms. References: Understanding Cisco TrustSec1.