In the traditional and hardware-based networking architecture, we configure everything at the device itself like switch or router. This approach will force organization to stick only to one vendor to avoid incompatibility issues and thus causes vendor-locking problems. However, with the introduction of virtualized networking the way network devices are configured and managed is completely changed.
Software-Defined Networking (SDN) is a new paradigm to network operation, design, configuration and management that models flexibility and automation into the networking fabric. Unlike the traditional networking, the software-based SDN architecture allows dynamic network configuration and management. This facilitates automation, virtualization, a holistic management and centralized view of the network architecture.
The SDN architecture is comprised three distinct and interactive layers
- Data Plane (Infrastructure Layer): This layer contains the networking infrastructure including the switches, the routers, the data and the process of forwarding data to its destination. Due to this reason, this layer is sometimes referred to as the forwarding plane.
- Controller Layer (Control Plane): This the intermediary layer between infrastructure and application layers and intelligently determines how traffic should flow.
- Application Layer (Application Plane): This layer includes all the network services and applications that interact with the control layer with the aim of specifying its needs and requirements.
The purpose of the SDN architecture is to separate the infrastructure layer from the control layer on networking hardware devices to reduce management complexity and greatly increase flexibility.
The SDN architecture Virtualized networking concepts has opened the door for further innovation and for other technologies to follow suite as well. The most common ones include the introduction of virtual storage area network (vSAN), software defined storage (SDS), software defined security (SDN), and software defined wide area networks (SD-WAN), just to name a few.