Hello,
You've raised some great questions about Software Defined Networking (SDN), and I'd be happy to clarify some of those points for you.
Traditionally, network configurations are manually adjusted using a command-line interface (CLI). These settings are static and need to be reconfigured manually to meet changing needs. However, SDN brings a significant shift in this approach. It separates the network control plane (that decides where the traffic is sent) from the data plane (that forwards traffic to the selected destination). This separation allows for a central, programmable controller to manage the entire network.
Here are some key differences between SDN and traditional networking methods:
1. Centralization of control: In SDN, a central controller has a comprehensive view of the entire network, which is usually not the case in traditional networks.
2. Programmability: An SDN controller is programmable and allows for automated network configurations. This isn't typically possible with traditional networking methods that involve manual configurations.
3. Flexibility: SDN allows for dynamic, on-the-fly adjustments to network traffic flow, providing greater flexibility than static, manual configurations found in traditional networking.
4. Vendor Neutrality: SDN is not tied to the hardware. You can program SDN onto any commodity hardware, unlike traditional networking that might require specific, proprietary devices from vendors.
SDN can bring a variety of benefits to businesses and organizations:
1. Scalability: As SDN allows for programmable and centralized control, it facilitates easier network scaling as businesses grow or requirements change.
2. Efficiency: The programmable nature of SDN enables quicker adjustments to network configurations and reduces the effort and time needed for manual configurations.
3. Security: With a centralized view of the network, it is easier to identify and manage potential security threats with SDN.
As for practical case studies, the usefulness of SDN can be observed in data centers, cloud services, and Internet Service Providers (ISPs). For instance, Google is known to have implemented SDN to increase the efficiency of their Data Center Networks (it reported improving network utilization by up to 95%).
Lastly, I would encourage you to dive deeper into resources and online courses that further unveil the functionality, benefits, and use cases of SDN. I hope this gives you a clearer perspective. Please feel free to ask if you have more questions!