Data Center Fabric

Deploy a massively scalable, automated, and resilient data center fabric with the open, disaggregated power of OcNOS. Engineer your network for the demands of cloud, virtualization, and AI.

Discover Key Advantages in OcNOS Hybrid Cloud-Native DC Whitepaper

Modern DC Clos

A modern DC CLOS fabric, also known as a spine-leaf architecture, is the industry-standard blueprint for building a high-performance data center. It provides a faster, more resilient, and scalable foundation specifically engineered to handle the intense east-west traffic from today’s AI and cloud workloads.
Diagram showing the shift from North-South to dominant East-West traffic patterns in modern data centers.

Maximize Throughput and Performance

The non-blocking nature of the CLOS fabric ensures your network capacity is fully utilized, preventing traffic hotspots and allowing data to flow freely.

Predictable Low-Latency

With a fixed, two-hop path between any servers in the fabric, you get the consistent, ultra-low latency required to accelerate AI/ML and demanding workloads.

Scale Seamlessly and Cost-Effectively

The modular design lets you add capacity on demand simply by adding more switches, enabling a pay-as-you-grow model that avoids disruptive and expensive “rip-and-replace” upgrades.

What is a Non-Blocking Architecture?

A non-blocking architecture for the DC CLOS prevents internal congestion by ensuring the total uplink bandwidth from leaf switches to spine switches matches the aggregate bandwidth of all connected server ports. This 1:1 oversubscription ratio allows every server to transmit at line rate without creating bottlenecks, providing a predictable and high-performance network.

EVPN-VXLAN for DC CLOS

Your high-performance CLOS is the physical superhighway for your data, but your business services need to be deployed and scaled instantly, without being tied to specific racks or rows. EVPN-VXLAN creates secure, virtual “tunnels” over your physical network, giving you the freedom to run any service, anywhere, at any scale.

Deploy Workloads Anywhere, Instantly

Create a seamless Layer 2 network that stretches across your entire Layer 3 fabric. Place or move a virtual machine or container anywhere you have capacity.

Isolate Every Tenant and Application

Move far beyond the 4,000 VLAN limit and create up to 16 million logical networks. Build secure, completely isolated virtual networks running on the same shared physical infrastructure.

Maximize Uptime and Bandwidth

EVPN multihoming allows a server to connect to two switches in a resilient, active-active mode. Both links are always forwarding traffic – doubling available bandwidth

 

Learn More in OcNOS Hybrid Cloud-Native DC Whitepaper

Understanding the DC-CLOS Fabric Topology

This diagram illustrates a modern multi-POD Data Center CLOS Fabric utilizing VXLAN EVPN, powered by OcNOS DC. It highlights the physical IP Underlay and the virtual VXLAN Overlay, showing how different traffic flows are handled to ensure scalability, efficiency, and multi-tenancy.

OcNOS DC-CLOS Fabric diagram showing Intra-VNI, Inter-VNI, Inter-POD, and WAN traffic flows.

OcNOS DC-CLOS fabric illustrating key traffic flows

Underlay and Overlay Networks
The IP Underlay Network (gray lines) provides the physical, high-speed IP connectivity between all switches (Leaf, Spine, Super-Spine, Border Leaf). Above this sits the VXLAN Overlay (colored tunnels), a virtual network that carries tenant traffic independently of the physical topology, enabling network agility.

VXLAN Encapsulation / Decapsulation
Leaf switches act as VXLAN Tunnel Endpoints (VTEPs). When traffic from a server enters the fabric, the ingress Leaf encapsulates the original frame into a VXLAN packet (orange triangle). When the packet reaches the destination Leaf, it is decapsulated (yellow triangle), and the original frame is forwarded to the destination server.

Integrated Routing & Bridging (IRB)
IRB provides a distributed gateway function that enables routing between different virtual networks (VNIs). In this fabric, routing logic is handled on the Spine or Leaf switches (orange circle), allowing for the most efficient traffic path between subnets without needing a centralized router.

Traffic Flow: Intra-VNI (Layer 2)
The Intra-VNI flow (green line) shows traffic between servers within the same virtual network (e.g., VNI 100). This traffic is efficiently bridged at the Leaf layer. The source Leaf encapsulates the packet, sends it across the underlay to the destination Leaf, where it’s decapsulated and sent to the server.

Traffic Flow: Inter-VNI (Layer 3)
The Inter-VNI flow (purple line) shows traffic between different virtual networks (e.g., from VNI 100/VRF A to VNI 200/VRF B). The source Leaf sends the packet to a Spine switch, which performs IRB to route the packet between the VNIs before forwarding it to the destination Leaf.

Traffic Flow: Inter-POD & To WAN
The Inter-POD flow (light blue line) shows traffic crossing between separate PODs via the Super-Spine layer, ensuring scalability across the data center. For external communication, the To WAN flow (orange line) directs traffic through the Super-Spine layer to the Border Leaf, which acts as the gateway to the outside world.

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Powering Critical Workloads with OcNOS

An OcNOS-powered fabric is engineered to solve your biggest challenges. From accelerating AI to transforming your network economics, our solution provides the performance and freedom your business demands.

Accelerate Your AI Initiatives

OcNOS enables a lossless fabric tuned for the most intense workloads with support for RoCEv2 over a DCB-enabled network (PFC/ECN).

Deliver Scalable Cloud Services

With EVPN-VXLAN, you can automate service delivery and provide the stable, multi-tenant environment needed to grow your cloud business.

Lower TCO

Our disaggregated model separates network software from hardware, giving you the freedom to choose best-of-breed whitebox switches. drastically reducing TCO.

Simplify and Automate Operations

Drastically reduce operational overhead and accelerate deployments with model-driven automation: OpenConfig, NETCONF/YANG, and gNMI.

 
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Resources & Technical Documentation

Explore our technical documentation, customer stories, and solution guides to see how the OcNOS Data Center Fabric can transform your network.

Solution Briefs & White Papers

White Paper: Migrating to Hybrid Cloud-Native Data Center

Learn the strategies and benefits of migrating to a modern, cloud-native architecture with an open networking foundation.

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Solution Brief: OcNOS for AI Fabric

Discover the technical advantages of building a high-performance, lossless fabric for demanding AI/ML workloads with OcNOS.

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Solution Brief: Data Center Interconnect

Learn how to build scalable, high-performance connectivity between your data center locations with OcNOS DCI.

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Product & Technical Documentation

Product Page: OcNOS DC

Get an overview of our flagship Network Operating System for data center and cloud environments.

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OcNOS DC Feature Matrix

Explore the comprehensive list of protocols and features supported by the OcNOS Data Center platform.

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Hardware Compatibility List

Browse the extensive ecosystem of open, whitebox hardware platforms compatible with OcNOS.

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OcNOS VXLAN Blogs

Data Center Solution – EVPN with VXLAN

A detailed overview of VXLAN and EVPN in the context of OcNOS, discussing its architecture and implementation.

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IP Infusion Overlay ECMP

Learn about Overlay ECMP and its importance in modern data center networks.

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Overlay ECMP (Part 2)

A deeper dive into the technical specifics and implementation of Overlay ECMP in OcNOS.

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OcNOS CP: Introducing New Market Features

Learn about new OcNOS CP software bundles, including the EVPN-VXLAN bundle, offering upgrades from traditional L2 services.

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OcNOS – EVPN VxLAN Demo

Watch a video demonstrating BGP configurations for building DC-Clos fabric and setting up EVPN-VxLAN overlay services with OcNOS.

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EVPN-VxLAN Demo – Part 2

See how ARP/ND cache works in OcNOS EVPN-VXLAN Clos fabric and how MAC-Move scenarios are handled for VM mobility.

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OcNOS VM Downloads

OcNOS Virtual Machine (VM)

Get familiar with OcNOS, validate configurations, and test L2, L3, and MPLS features without bare metal switches. Available from 2025.

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Customer Stories & Videos

Customer Story: Scott Data

See how Scott Data, a Tier III Certified data center, deployed network disaggregation with IP Infusion OcNOS.

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Customer Story: Madeo

See how Madeo achieved greater flexibility and lower TCO by transitioning to an open data center network with OcNOS.

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Press Release: OcNOS AI Fabric with HYPERSCALERS

Learn how HYPERSCALERS built high-performance GPU-based services using OcNOS for their AI/ML workloads.

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OcNOS Video Tutorial

Watch our technical experts walk through key configurations and use cases for the OcNOS platform.

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Get Started Today!

Speak with an IP Infusion expert to discuss your specific needs and learn how we can help you unlock the full potential of your network with open networking solutions.

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