Virtual topologies built on top of an existing IP network. Articles tagged Overlay Networking cover VXLAN, EVPN, LISP and the encapsulation choices behind each fabric.
VRFs, VLANs, VXLAN, and LISP all segment a network at different layers. This decision framework shows what each one actually separates and when to use it, so you do not reach for a fabric when a VLAN would do.
The network no longer stops at the physical switch port. Hypervisors, virtual switches, and VM networking explained for engineers who know networking but not the compute side, where your VLANs actually terminate.
The hard engineering in SD-Access adoption is the border where the fabric meets your existing campus. This covers how VXLAN and LISP traffic crosses that boundary and the realistic migration paths that keep users up.
SD-Access is LISP as the control plane, VXLAN as the data plane, and Catalyst Center operating the whole thing. This article explains the fabric architecture, its roles, and the policy model, extending the network virtualization cluster.
VXLAN without a control plane is flood-and-learn, and that does not scale to a real data center. BGP EVPN is what fabrics actually use: what it advertises, the route types that carry reachability, and why it replaced flooding everywhere.
VXLAN stretches Layer 2 across a routed network by wrapping Ethernet frames in UDP. This deep dive takes the encapsulation apart to the byte level with a real crafted-and-decoded packet, covering VNIs and VTEPs.
An IP address is both identity and location, and that overload breaks mobility. LISP splits the two into separate namespaces. This post explains the protocol and proves it on a real IOS XE lab, from first dropped packet to clean flow.