What Is VMware VXLAN and How Does It Improve Network Virtualization?

Traditional VLANs are limited to 4096 segments, which limits how far large data centers can scale. VXLAN gets around this with a 24-bit VXLAN Network Identifier (VNI) that supports up to 16 million isolated logical networks. That makes it a good fit for multi-tenant cloud environments that need a lot of network segmentation and room to grow.

VXLAN uses an underlay and an overlay. The underlay is the existing physical Layer 3 network that routes IP traffic. The overlay network sits on top of it, and the virtual Layer 2 segments live there. VXLAN Tunnel Endpoints (VTEPs) encapsulate and decapsulate traffic between virtual machines on different hosts, and each VTEP uses its physical IP address to set up VXLAN tunnels.

This design separates the virtual network from the physical infrastructure. Administrators can design tenant networks without being limited by physical switch configurations. VM mobility gets simpler, tenants are better isolated from each other, and physical switches have fewer MAC addresses to learn.

Overall, VXLAN gives virtualized data centers more scalability, more flexibility, and better network isolation.

Q1: What problem does VXLAN solve?

It removes the VLAN scalability limits and improves network isolation in large virtual environments.

Q2: What is a VNI?

A VXLAN Network Identifier, which uniquely identifies each logical overlay network.

Q3: What is a VTEP?

A VXLAN Tunnel Endpoint, which encapsulates and decapsulates traffic between virtual machines.

Q4: Does VXLAN replace the physical network?

No. It runs as an overlay on top of the existing Layer 3 physical network.