Over the last year, the hottest topics in networking have been software-defined networking (SDN) and Network Virtualization (NV) but Software-defined networking (SDN) is still a relatively new model used to design, build, and manage networks but have gained tremendous momentum because at least six of the largest networks in the world like Google, Facebook, Verizon etc, are supporting it. So lets have a look what the SDNs are and their benefits.
Software-Defined Networking (SDN) is an emerging architecture that is dynamic, manageable, cost-effective, and adaptable, making it ideal for the high-bandwidth, dynamic nature of today’s applications.
Basically, software-defined network attempts to build a computer network by separating it into two systems.
The first system is the control plane which proivdes performace and fault mangement via net flow IP fix SNMP and other standard protocols. It typically handles cofiguration managament of the SDN compliant devices and understands the network topology loaded with these details. The controller can process connection requests based on desired requirement such as QoS levels. The controller can also perform link management between devices.
The second system is the data plane which is responsible for forwarding traffic to the selected destination. Switches can either be reliant on the controller to make forwarding decisions or make the decisions on their own. The control plane configures connection paths or flows into the data plane through the use of a control protocol.
The control protocol is used by the controller in a software-defined network to perform important functions such as connection setup. When a host attempts to communicate with another host over an SDN, the first packets from the client involved with the new flow are used to determine whether or not a forwarding decision can be made locally by the switch or if the switch needs to ask the controller what to do. If the switch determines that it must ask the controller, it will do so via a secure channel using the control protocol.
Benefits of SDN
- Inexpensive switches that have very little resident software and processing needs.
- Centralization of the forwarding information base.
- SDN dynamically respond to application requirements.
- Optimization of utilization of the network without sacrificing service quality SDNs.
- SDNs can filter packets as they enter the network and hence can act as simple firewalls at the edge of the network.
- SDNs switches can redirect certain suspicious traffic flows to higher layer security controls such as IPS systems,application firewalls and data loss prevention devices.
- It can be used as a simple cost-effective load balancing device.
- SDNs controllers can be clustered for fault tolerance and high availability.