Overview
Software-Defined Networking (SDN) is a paradigm shift in networking that moves the 'intelligence' of the network from individual hardware devices (like switches and routers) to a centralized software-based controller. This allows for more flexible, scalable, and automated network management.
Key Concepts
- Control Plane: The 'brain' of the network that makes decisions about where traffic is sent.
- Data Plane (Forwarding Plane): The underlying hardware that actually moves the packets based on instructions from the control plane.
- Southbound APIs: Protocols (like OpenFlow) used by the controller to communicate with the hardware.
- Northbound APIs: Interfaces used by applications and orchestration tools to communicate with the SDN controller.
Benefits
- Centralized Management: View and control the entire network from a single interface.
- Agility: Rapidly deploy and change network configurations via software.
- Cost Efficiency: Use lower-cost 'white-box' hardware while maintaining advanced features in software.