A Hierarchical Traffic Offloading Mechanism for End-to-End Reliability in a Multihop Multiconnection Wireless Sensor Network

The proliferation of wireless terminal devices and services has highlighted the significance of multihop and multiconnection wireless sensor networks (MHMC-WSNs). However, many challenges have arisen in maintaining effective throughput and end-to-end (E2E) reliability for remote users as the number of hops and connected nodes of relays increases significantly. A cross-layer analysis approach to assess the E2E reliability of MHMC-WSN is proposed in this article, in which a transmission model based on offloading regions is presented, giving a closed-form solution for both uplink and downlink outage probability in a heterogeneous network. Taking both transmission and scheduling into account, a cross-layer caching queuing model is proposed along with queuing delays analysis for both E2E link and relay nodes. Finally, a hierarchical traffic offloading mechanism (HTOM) is proposed, consisting of a grouping-routing strategy and a dynamic off-load scheduling method. Best-response Stackelberg game (SG) and Lyapunov drift-plus-penalty (DPP) optimization theory are utilized to address long-term optimization challenges and slot-by-slot optimization problems in multirelay scenarios. A 5G-Wi-Fi simulation system for MHMC-WSN is developed to evaluate the E2E transmission reliability and performance of HTOM.