Software-defined networking
administrators to programmatically initialize, control, change, and manage network behavior dynamically via open interfaces[1] and provideabstraction of lower-level functionality. SDN is meant to address the fact that the static architecture of traditional networks doesn't support the dynamic, scalable computing and storage needs of more modern computing environments such as data centers. This is done by decoupling or disassociating the system that makes decisions about wheretraffic is sent (the SDN controller, or control plane) from the underlying systems that forward traffic to the selected destination (thedata plane).
SDN was commonly associated with theOpenFlow protocol (for remote communication with network plane elements for the purpose of determining the path ofnetwork packets across network switches) since the latter's emergence in 2011. Since 2012,[2][3] however, many companies have moved away from OpenFlow, and have embraced different techniques. These includeCisco Systems' Open Network Environment and Nicira's network virtualization platform.
SD-WAN applies similar technology to a wide area network (WAN).[4]