Optimizing The Access Control System for IOTA Tangle: A Game-Theoretic Perspective

Abstract

With the development of Internet of Things (IoT) applications, there is an explosion in demands for data sharing between IoT nodes, which needs the IoT network to provide a data sharing platform to enhance data privacy and security. IOTA Tangle has been considered as a promising Distributed Ledger Technology to establish such a platform because of its affinity to IoT nodes. Additionally, Tangle proposes an access control system to prevent congestion of the platform by allocating a number of tokens to each node, and limiting data sharing rate of each node based on its hold tokens. However, this poses an inconspicuous but fatal problem that high-rate-demand nodes with few tokens cannot acquire an ideal rate. In this paper, we optimize the access control system for the Tangle-based platform by setting a token transferring mechanism, where a chaebol node can sell tokens to provide IoT nodes with ideal data sharing rate. Since the chaebol node needs more profits and IoT nodes need ideal data sharing rate, we formulate the token pricing and purchasing problem as a two-stage Stackelberg game. We analyze the equilibrium of the game in a uniform pricing scheme and design an access control algorithm TTM based on the equilibrium. Finally, we verify performance of the algorithm by experiments. The results show that the proposed algorithm outperforms the state-of-art in terms of providing high-rate-demand nodes with the ideal rate.