In both scenarios, big data plays a key role in requiring SDNs or network programmability. SDNs can help steer traffic between thousands of servers processing massive datasets in parallel; and can help data center networks scale more efficiently while maintaining server-to-server, server-to-storage, and server/storage-to-network connectivity.
Whatever the requirement, today's networks are not up to the task of providing the adaptability and scale that SDNs promise, according to the ONF:
"The explosion of mobile devices and content, server virtualization, and advent of cloud services are among the trends driving the networking industry to reexamine traditional network architectures. Many conventional networks are hierarchical, built with tiers of Ethernet switches arranged in a tree structure. This design made sense when client-server computing was dominant, but such a static architecture is ill-suited to the dynamic computing and storage needs of today's enterprise data centers, campuses, and carrier environments."
Read more about data center in Network World's Data Center section.