Enterprise Network Architecture
This chapter covers enterprise campus design models, the separation of network planes, Cisco SD-Access fabric concepts, and wireless deployment models. These architectural foundations frame how the rest of the ENCOR topics fit together.
Hierarchical campus design
The classic three-tier model separates the access layer (connects end devices), the distribution layer (aggregates access switches, enforces routing policy, and provides redundancy), and the core (high-speed transport between distribution blocks). Smaller sites use a collapsed-core design where distribution and core functions merge into one layer.
Network planes and SD-Access
Devices separate the control plane, which runs protocols and builds forwarding tables, from the data plane, which forwards user packets using those tables. Cisco SD-Access builds on this idea: a LISP-based control plane maintains an endpoint-to-location mapping database, VXLAN forms the data-plane overlay, and scalable group tags carry policy independent of IP addressing.
Wireless deployment models
In a centralized local-mode design, lightweight APs tunnel traffic to a wireless LAN controller over CAPWAP, centralizing forwarding and policy. FlexConnect can switch some traffic locally at a branch, and autonomous APs operate standalone without a controller. The deployment model chosen affects where traffic is switched and how policy is applied.