Bandwidth Allocation with Slice Quality Fairness in Network Slicing under Variable Link Capacity

Network slicing has been proposed to meet the diverse requirements of mobile applications. In a wireless environment with fluctuating link capacity, we need to adjust each slice's bandwidth dynamically according to the capacity while maintaining the user experience. In addition, network operators need to consider the out-of-slices users when the link capacity is insufficient for slicing. The traditional best-effort control does not allocate the bandwidth to them because it prioritizes the slice users. We set a utility function, called slice quality, for each slice based on its requirement and adjust each slice's bandwidth depending on the variable link capacity to keep these qualities fair. We define linear utility functions for the normal slice, which has a fixed bandwidth requirement called SLO, and exponential utility functions for the residual slice, which manages the out-of-slices bandwidth. The experiment results based on the real cellular trace show that we can improve the slice quality's fairness by 56% compared to a simple bandwidth allocation policy while keeping the quality degradation of normal slices below 11%.