Cloud Offloading with QoS Provisioning Using Cross-Layer Network Coding
Mohammed S. Al-Abiad, Sameh Sorour, Md. Jahangir Hossain · 2018
In this paper, we consider the use of cross- layer network coding and fog radio access networks (F- RANs) as a means to jointly optimize users quality-of-service and offload the cloud servers and cellular macro base- stations. Multiple edge nodes called enhanced remote radio heads (eRRHs) are connected to a central unit known as cloud base station (CBS). The transmit frame of each eRRH consists of multiple resources blocks called power zones (PZs), each fixed at a pre-assigned power level. The various ergodic capacities of different users at different PZs/eRRHs and the CBS bring a new trade-off between the number of multiplexed users and the transmission rates of each PZ and each CBS allocated channel. The proposed framework incorporates such information in the network coding decisions. As such, the multiplexed users, encoded files, and transmission rates of each PZ/eRRH and each CBS allocated channel maximizes the throughput which is defined as the number of correctly received bits and actual CBS physical-resource offloading, respectively. The problem is first formulated using graph theory techniques, and its intractability is shown. Given the difficulty of the problem, the paper proposes a heuristic approach by dividing it into two sequential subproblems and solving each subproblem efficiently. Presented simulation results reveal that the proposed solution achieves small offloading performance degradation compared to the cross-layer QoS unaware scheme but largely maximizes the received throughput compared to the state-of- art algorithms.