Future 5G networks will bring the concept of network programmability beyond what is now possible
with SDN. While SDN splits routing and forwarding capabilities of a switch and reassigns the former
to an SDN controller, this split between logic and agent should be performed for any NF, including
the ones related to the CP. That is, the SDN principles are extended to all control and data layers as
well as management functions usually deployed in mobile networks. An example of this view is
depicted in below Figure , in which an enhanced controller extends the SDN capabilities to different
kinds of functions in the network.
The following three categories can be identified:
(i) networking control functions (e.g., mobility and session management, and potentially QoS/QoE control);
(ii) connectivity control functions (mainly packet forwarding or SDN‐based packet forwarding);
and (iii) wireless control functions (e.g., radio link adaptation and scheduling).
This last category, however, may not be fully implemented using a software‐defined approach, for instance due to scalability reasons.
The Reference :
5G System Design
Architectural and Functional Considerations and Long Term Research
