18. Mobile Data Offloading Through Third-Party Wi-Fis: Association Rules and Incentive Mechanisms

WiFi offloading is regarded as one of the most promising techniques to deal with the explosive increasing data usage over the existing 4G cellular network due to its high quality of service, high data transmission rate, and low requirement on devices. In this chapter, we investigate two key issues, i.e., association rules and incentive mechanisms, for data offloading through third-party WiFi access points (APs) in a cellular mobile system. Firstly, by assuming the data offloaded through the third-party WiFi AP is charged based on usage, we formulate the user association problem as an utility maximization problem from the cellular operator’s perspective. By considering whether the successive interference cancelation (SIC) decoders are available at the BS and/or the WiFi AP, different utility functions are considered. Then, the optimal user association rules are derived for each case when the number of users is large. Secondly, incentive mechanisms to motivate WiFi APs to provide data offloading services are studied. In particular, a salary plus bonus-based incentive mechanism is proposed. Under the proposed incentive scheme, WiFi APs are rewarded not only based on the amount of offloaded data but also based on the quality of the offloading service. The interactions between the WiFi APs and the mobile network operator are investigated using Stackelberg game.