SDN Controller
The brain of Software-Defined Networking, enabling centralized control, programmability, and automation of modern networks.
What is an SDN Controller?
The SDN Controller sits at the heart of an SDN architecture, separating the control plane from the data plane. It communicates with applications through northbound APIsand with networking devices using southbound APIs. This centralized intelligence makes networks more flexible, programmable, and secure.
Application Layer
Network apps like firewalls, IDS, and load balancers communicate policies.
Control Layer (SDN Controller)
The brain of the network: central decision-making & abstraction.
Infrastructure Layer
Physical/virtual switches and routers that forward packets.
Models of SDN Controllers
Open SDN
Uses OpenFlow protocol for direct control of switches.
API-based SDN
Uses REST APIs, SNMP, or CLI for programmability.
Hypervisor-based Overlay
Creates virtual overlays without changing physical devices.
Hybrid SDN
Combines traditional networking with SDN.
Evolution of SDN Controllers
2008
Introduction of OpenFlow as first SDN control protocol.
2011
Emergence of open-source controllers (NOX, Floodlight).
2014
Enterprise-grade controllers like OpenDaylight & ONOS.
2020+
Cloud-native and AI-driven SDN controllers for automation.
SDN Controller vs Traditional Networking
| Aspect | SDN Controller | Traditional Networking |
|---|---|---|
| Control | Centralized via controller | Distributed in devices |
| Programmability | Highly programmable via APIs | Vendor-specific CLI |
| Flexibility | Dynamic and scalable | Static and rigid |
| Security | Global visibility & enforcement | Device-level security only |
Use Cases of SDN Controller
Data Centers
Centralized management and rapid provisioning of virtual networks.
Cloud Networking
Scalable cloud interconnects with automation and agility.
Telecom Networks
Efficient traffic engineering, slicing, and 5G orchestration.
Enterprise WAN
Simplified branch connectivity and secure access policies.
Benefits of SDN Controller
Centralized Control
Manage the entire network from a single dashboard with unified policies.
Programmability
Easily automate network behavior using APIs and software logic.
Enhanced Security
Apply consistent security rules across devices and monitor traffic centrally.
Agility & Speed
Deploy applications and services faster with dynamic network adjustments.
SDN Controllers
AIS800-640
64 x QSFP800 switch ports with Tomahawk 5. High-performance, low-latency switch for data centers.
AIS800-1280
128 x QSFP800 ports, ideal for ultra-dense AI workloads and cloud infrastructure.