Delay Fairness in 5G Networks with SD-RAN

The possibility of decoupling the operation of control plane from data plane in RANs, which became possible with the introduction of Software-Defined Networks in 5G, brought a paradigm shift in cellular network operation. The key element that enables this is a centralized controller, located away from base stations. This yields increased flexibility in the functioning of cellular networks, resulting in considerable enhancements compared to classical pre-5G resource allocation approaches. However, so far the range these improvements span is known only in terms of throughput. The advantages in terms of other metrics and objectives, like delay fairness, are not yet known. Therefore, in this paper, we derive analytically the resource allocation policies that lead to different delay fairness definitions among the entities in an SD-RAN-enabled network and show the advantages compared to the classical pre-5G approaches. We do this for different scenarios. First, we consider the minimum potential delay fairness in the network. Then, we consider the min-max delay fairness among base stations, and also the min-max delay fairness among users. We evaluate performance extensively with input data from a dataset. The results indicate that the introduction of SD-RAN improves the objective value up to 6× compared to policies without SD-RAN.