What Does Southbound API Mean in 200-301?
Also known as: southbound interface, SBI
Quick Definition
APIs on an SDN controller that communicate with and programme the network devices below.
Full Definition
Southbound APIs are used by the SDN controller to push configuration and forwarding rules down to network devices. Examples include OpenFlow (programmes flow tables), NETCONF (using YANG data models over SSH), RESTCONF (HTTP-based NETCONF alternative), and gRPC. The controller uses southbound APIs to tell each device what traffic to forward and how.
Exam Trap — Don't Get Fooled
Southbound = toward devices (below the controller). NETCONF uses SSH (TCP port 830) and YANG data models. RESTCONF is the HTTP-based alternative to NETCONF. Both are examples of southbound interfaces.
Related 200-301 Terms
An architecture that separates the network control plane from the data plane, enabling centralised programmability.
APIs on an SDN controller that allow applications and management tools to communicate with the controller.
Cisco's SDN controller and network management platform providing centralised automation and analytics.
Frequently Asked Questions
What does Southbound API mean on the 200-301 exam?
Southbound APIs are used by the SDN controller to push configuration and forwarding rules down to network devices. Examples include OpenFlow (programmes flow tables), NETCONF (using YANG data models over SSH), RESTCONF (HTTP-based NETCONF alternative), and gRPC. The controller uses southbound APIs to tell each device what traffic to forward and how.
How does Southbound API appear as a trap on the 200-301?
Southbound = toward devices (below the controller). NETCONF uses SSH (TCP port 830) and YANG data models. RESTCONF is the HTTP-based alternative to NETCONF. Both are examples of southbound interfaces.
How important is Southbound API on the 200-301 exam?
Southbound API falls under the Automation domain of the 200-301 exam. Understanding it in context with related terms like northbound-api and sdn is essential for answering scenario-based questions correctly.