Reading - The road to SDN: An Intellectual History of Programmable Networks

Question 1

Describe the differences in the terms network virtualization and software defined networking (SDN). How can we use network virtualization to evaluate and test SDNs?

Answer 1

Network Virtualization refers to abstracting the network away from the physical equipment, which can be accomplished without SDN (we did this in Project 1 using Mininet!). On the other hand, SDN refers separating the control plane from the data plane by using a centralized logic controller. SDN does not necessarily imply Network Virtualization is employed.
Network virtualization software like Mininet allows SDNs to be tested in a virtual environment by using logical processes to emulate physical network devices, including OpenFlow capable switches. By emulating the physical equipment, control plane logic for an SDN can be tested without the need for physical equipment and complicated data collection methods.