Shaping the network traffic with a new approach in designing and managing is SDN. It is a comprehensive and sophisticated method of controlling the network with functional separation, its virtualization and automation to attain best possible optimization level.
Just as in cloud data centers , which we use for server’s virtualization with infrastructure services , the term SDN covers numerous types of network to keep it active , flexible , scalable through virtualization and traffic shaping . With the separation of network functions in control planes (routing path) and forward planes (data path), a network administrator can shape the traffic as per requirement (as and when needed) from a centralized console without working on individual switches or any type of additional connectivity. The target of SDN is to address organization’s IT requirements as early as possible through programmability.
How it works?
Unlike cloud providers who offers complex cloud platforms , SDN providers offers simple architectures, having methodology of controlling network centrally by splitting the control logic without affecting the computer resources ( network switches or routers ) i.e. split tunneling . All SDN models have some version of an SDN Controller, such as OpenFlow or open virtual switch database (OVSDB),with southbound APIs and northbound APIs.
- Controllers: separates the packet forwarding and high-level routing decisions.
- Southbound APIs: use to pass on information to network devices.
- Northbound APIs: use to connect with the applications and business logic.
The SDN Framework:
Open Flow & SDN
Although Open flow is not covering the complete SDN architecture, but it works in a high extent with SDN architecture. It is basically a protocol to communicate controller with open switch to enable the control plane interaction with forwarding plane. It is being used to define packet-received, packet out, modification of forwarding packet, and get statistics.
The Benefits of SDN
Along with the centralized control of the network; we can achieve following further benefits as well:
- Reducing the Capital expenditure:with SDN, we can have a cost-effective network implementation scope because of limited purchasing of networking hardware and further it supports pay-as-you-need models.
- Reducing the Operational expenditure:as mention above, due to network element’s algorithmic control, we can easily scale the network. It enable us to automate the processes.it is reliable and available by reducing management and human errors.
- Agile and Flexible:it help organizations to deploy rapidly different applications, services, and infrastructure as and when required.
- Bond and orchestrate: it can aggregate the bandwidth and provides session continuity and grooming traffic with QoS.
- Network Virtualization : it is an SDN data center application , supports random assignment of IP/MAC addressing schemes, at the same time it automate the network configuration for expected network segmentation.