Campus → VLANs + STP + 802.1X + HSRP + OSPF Branch → IPSec + SD-WAN + BGP + simple VLANs  Enterprise → BGP + MPLS + SD-WAN OMP + IPSec + OSPF  DC → eBGP (underlay) + VXLAN + EVPN (overlay) SP → IS-IS + BGP (full table) + MPLS + SR-MPLS/SRv6 + EVPN L2VPN + L3VPN