Software-defined networking (SDN) is designed to make networks more flexible and agile. SDN was originally defined as an approach — to designing, building, and managing networks — that separates the network’s control and forwarding planes, enabling network control to become directly programmable, and the underlying infrastructure to be abstracted for applications and network services.
SDN is redefining the network architecture to support the requirements of the forthcoming 5G ecosystem—5G SDN will play a crucial role in the design of 5G wireless networks. In particular, 5G SDN will provide an intelligent architecture for network programmability, as well as the creation of multiple network hierarchies.
5G SDN Network Programmability
The main idea behind SDN is to move the control plane away from network hardware and enable external control of data through a logical software entity called a controller. The controller, which manages packet-flow control to enable intelligent networking, is situated between network devices and applications. In this architecture, network control becomes programmable. With the controller, administrators will be able to easily manage the 5G network and introduce new services or changes.
For this reason, the 5G SDN paradigm will allow an increase in the flexibility and programmability of 5G networks, bridging the gap between business needs and management systems. An intelligent, virtualized, programmable 5G network will enable providers to innovate, both in their operations and in their service offerings. They will be able to deliver new services on demand, thereby improving their overall efficiency.
5G SDN Multiple Hierarchies
An essential part of 5G technology will be the creation of multiple hierarchies that compose the network topology. Compared with today’s flat core networks, 5G creates hierarchical cores. “Think of it as a multiple hierarchy of caches,” says Raj Singh, general manager of the wireless broadband group at Cavium. Similar to content delivery networks, which cache popular content at the edge, 5G will cache content locally; but it will require an SDN controller to manage the traffic and orchestrate how the devices communicate.
Hundreds of nodes may send data to a 5G SDN controller. The different hierarchies will contain RAN radios of different sizes. Also, depending on the geographic locale, the network will have different degrees of hierarchy. The multiple hierarchies and 5G SDN controller will allow traffic to be shifted dynamically based on need.
5G SDN Advantages
The value of 5G SDN — particularly in combination with network functions virtualization (NFV) and virtualized network functions (VNF) — is its ability to provide network virtualization, automation, and create new services on top of virtualized resources. In addition, 5G SDN network programmability enables new business models and drives revenue growth. The 5G SDN architecture will be dynamic, highly manageable, and cost-effective, making it perfect for the dynamic, high-bandwidth nature of 5G use cases.