What is Software Defined Networking? (SDN)
Software-Defined Networking (SDN)
The idea of programmable networks has newly re-gained substantial momentum due to the emergence of the Software-Defined Networking (SDN) paradigm. Outdated network architectures are ill-suited to meet the requirements of today’s enterprises, carriers, and end users. SDN often referred to as a key enabler that promises dramatically simplify network management and enable innovation through network programmability.
Software Defined Networking (SDN) is an emerging network framework where network control is decoupled from forwarding and is directly programmable. Previously, the network control is firmly bound in individual network devices. This way is dramatically changed into accessible computing devices enables the underlying infrastructure to be abstracted for applications and network services, which can treat the network as a logical or virtual entity.
Fig 1: Software-Defined Network Architecture
Figure 1 represents a logical view of the SDN framework. Network brainpower is logically integrated in software-based SDN controllers, which maintain a global view of the network. SDN also significantly simplifies the network devices themselves, as they no longer need to understand and process thousands of protocol standards but only accept instructions from the SDN controllers.
OpenFlow is the first standard communications interface defined between the control and forwarding layers of an SDN framework that allows to direct access and manipulation of the forwarding plane of physical as well as virtual network devices.
SDN architecture will provide a set of Application Programming Interfaces (APIs) that simplifies the implementation of common network services like routing, multicast, security, access control, bandwidth management, traffic engineering, QoS, energy efficiency, and various forms of policy management. Therefore, enterprises, network operators, and carriers gain exceptional programmability, automation, and network control, enabling them to build highly scalable, flexible networks that cheerfully familiarize to changing business needs.