Cisco SDA Deep Dive: How LISP, VXLAN, and TrustSec Work Together in the Fabric in 2026
Cisco Software-Defined Access (SDA) is a three-plane fabric architecture that replaces traditional campus designs — spanning tree, HSRP, manual VLAN trunking — with a fully automated, identity-aware overlay network. LISP handles the control plane, VXLAN handles the data plane, and TrustSec handles the policy plane, all orchestrated through Catalyst Center. Key Takeaway: Understanding how LISP, VXLAN, and TrustSec interact at the packet level is what separates engineers who can troubleshoot SDA fabrics from those who just click buttons in Catalyst Center — and it’s exactly what the CCIE Enterprise Infrastructure lab tests. ...