Figure 3
From: Building programmable wireless networks: an architectural survey
Comparison of traditional and SDN network architectures. (a) In traditional networking, the control planes (CP) and the data planes (DP) are colocated on devices to ensure decentralized network control. (b) In SDNs, the DPs and CPs are separated with a centralized controller controlling multiple DPs while supporting a southbound API to the DPs and a northbound API to the SDN applications.