VXLAN vs MPLS: Why VXLAN Is Gaining Preference in Metro and Wide‑Area Networks

Recent advances in cloud computing, virtualization, and containerization have accelerated the adoption of network virtualization technologies. Both MPLS and VXLAN apply virtualization ideas to express logical network architectures, but they address different requirements.

What is MPLS? Multiprotocol Label Switching (MPLS) uses short path labels to forward packets efficiently across an open network, supporting multiple network‑layer protocols and data‑link technologies. It simplifies node‑to‑node transport, requires minimal configuration to add sites, and can operate independently of IP, with MPLS‑over‑VPN adding an extra security layer.

What is VXLAN? Virtual Extensible LAN (VXLAN) encapsulates Layer‑2 Ethernet frames inside UDP packets on a Layer‑3 underlay, allowing devices to communicate as if they were on the same Ethernet segment. VXLAN builds an overlay network on top of existing IP underlays, solving scalability challenges of large cloud deployments.

Compared with MPLS, VXLAN is newer and addresses scalability for large data‑center environments. Three main reasons make VXLAN more attractive for data‑center networks:

Routers that support MPLS are generally more expensive than three‑layer data‑center switches that support VXLAN.

MPLS‑based VPN solutions require tight coupling between edge and core devices, forcing every node in a data‑center network to support MPLS.

Skilled MPLS engineers are scarce, whereas VXLAN is simpler and widely mastered by network engineers.

Modern data‑center switches (e.g., Broadcom Trident 3/4) provide hardware‑assisted VTEP support for line‑rate VXLAN encapsulation and expanded tables for large‑scale routing and forwarding, enabling VXLAN‑based metro and WAN deployments without costly MPLS routers.

VXLAN Overlay Architecture for Metro/WAN Overlay networks are loosely coupled to the underlay, allowing any capable IP network to serve as the transport. This flexibility mirrors SD‑WAN benefits and enables Ethernet‑line (E‑Line), Ethernet‑LAN (E‑LAN), and L3VPN services over a VXLAN overlay.

Control‑Plane Options Since VXLAN does not prescribe a control plane, several options exist:

BGP EVPN : a protocol‑based approach that requires configuration on each edge node but adds operational complexity.

SDN‑based control : a centralized controller programs the data plane, reducing BGP EVPN complexity but raising scalability concerns for large metro/WAN deployments.

Distributed (de‑centralized) SDN : controller functions are replicated across the network, eliminating a single‑point controller while retaining simplified service provisioning.

These options are compared in the table below (Figure 1).

Deployment Advantages Because VXLAN decouples overlay services from the underlay, it enables deployment scenarios that MPLS cannot match, such as adding new Ethernet or VPN services at the network edge without altering the existing IP fabric.

The illustrated metro‑network infrastructure can support all services traditionally delivered over MPLS—commercial Internet, Ethernet, VPN, and triple‑play—while eliminating MPLS’s cost and complexity.

In summary, VXLAN’s hardware support, lower equipment cost, simpler engineering, and flexible overlay capabilities make it a compelling alternative to MPLS for modern metro and wide‑area network deployments.