What Does Software-Defined Networking (SDN) Mean?
Software-defined networking (SDN) is a newly emerging computer networking architecture. Its main distinguishing factor is the separation of the data plane from the control plane in routers and switches. In other words, the control is decoupled from hardware and implemented in software. Under this architecture, the implementation of the control plane is via software within the servers and is separate from networking equipment, while the data plane is implemented within networking hardware or equipment. The best example of this architecture is OpenFlow.
Techopedia Explains Software-Defined Networking (SDN)
To understand software-defined networking better, first we must look at how traditional networking architecture treats data packets. When a data packet arrives at a switch or router, the firmware tells the hardware where to forward the packet and sends all packets to that destination via the same path. In other words, it treats all packets in the same fashion. More advanced smart switches equipped with application-specific integrated circuits (ASICs) can recognize different types of packets and treat them differently based on the ASICs are programmed. The problem is that these solutions are quite expensive.
