A Study Of Trading Incentives For D2D Content Sharing In Mobile Edge Caching Networks

With the widespread popularity of various mobile devices,mobile network data traffic has shown explosive growth,making the backhaul links of existing mobile network architecture carry heavy communication pressure.To ease the backhaul link burden,Mobile Edge Caching(MEC)networks assisted by D2D(Device-to-Device)technology have emerged.This network uses the storage space of edge or user devices to cache files on these devices in advance,and when users request content of interest,they can get it from these devices via D2 D links,thus reducing the load on base stations and backhaul links.However,content sharing brings about device resource consumption,and users prefer to obtain content from the network only and avoid content sharing,which directly affects the overall performance of MEC networks.To address this problem,this paper proposes an auction-based incentive mechanism for D2 D content sharing transactions and a blockchain-based incentive mechanism for D2 D trusted content sharing transactions.The theoretical analysis shows that the proposed incentive mechanism maintains the economic characteristics of individual rationality,incentive compatibility and budget balance,and the experimental results also demonstrate the effectiveness of the proposed mechanism.The details are as follows:(1)For the problem of content trading and pricing between a single content requester and multiple content providers,a D2 D content sharing transaction incentive mechanism based on reverse auction is proposed.First,a single-buyer-multi-seller reverse auction model is used to integrate the effects of the remaining power of user devices and the supply and demand of traded content on the pricing of transactions.Second,based on the model,the objective function of maximizing network utility is derived,and an auction algorithm consistent with content trading is proposed to aggregate content sharing behavior among users.Finally,a theoretical analysis of the economic characteristics of the mechanism is given.(2)For the problem of content trading and pricing between multiple content requesters and multiple content providers considering social relationships,a bilateral auction-based incentive mechanism for D2 D content sharing transactions is proposed.Firstly,a user preference model is established by combining user social relationships and a multi-buyer-multi-seller bilateral auction model is used to obtain a total network utility function that takes into account valuation and transaction costs.Second,considering the influence of user preferences on transaction matching,a buyer’s optimal stable matching algorithm based on user preferences is proposed;for the problem that the buyer’s optimal stable matching algorithm cannot maximize the network utility,an optimal stablematching algorithmbased on minimum weights and an approximate VCG(Vickrey-Clerke-Groves)pricing scheme based on the base payment price are proposed.Finally,a theoretical analysis of the economic characteristics of the mechanism is given.(3)For the problem of untrustworthiness in the process of D2 D content sharing,a blockchainbased incentive mechanism for D2 D content sharing transactions is proposed.First,in order to improve the trustworthiness of content sharing,a blockchain-based D2 D content sharing transaction framework is proposed.Second,considering the difficulty of deploying traditional consensus mechanisms on resource-constrained user devices,a lightweight consensus mechanism based on proof-ofinterest delegation is proposed;and,to address the latency problem brought by consensus mechanisms to content transactions,a joint optimization scheme based on two-stage contract theory is constructed to encourage D2 D users to contribute resources and consensus nodes to actively participate in block verification.Finally,in order to measure the quality of content sharing and block verification,two comprehensive evaluation metrics,content value and verification service value,are developed,and optimal transaction contracts are designed for each type of content providers and consensus nodes.