To appear in Proceedings of the Fifteenth IEEE International Conference on Computer Communications, INFOCOM 2020, Beijing, China
Abstract—Advances in mobile computing have paved the way for new types of distributed applications that can be executed solely by mobile devices on device-to-device (D2D) ecosystems. Representative examples are crowdsourcing, context-aware appli cations, computation offloading, and others. More sophisticated applications, like cryptocurrencies, need a distributed ledger to function. Distributed ledgers, such as blockchains and directed acyclic graphs (DAGs), employ consensus protocols like Proof- of-Work and Proof-of-Stake to add data in the form of blocks. However such protocols are designed for resourceful devices that are interconnected via the Internet. Moreover, existing distributed ledgers are not deployable to D2D ecosystems since their storage needs are continuously increasing. In this work, we introduce Mneme, a DAG-based distributed ledger that can be maintained solely by mobile devices and operates via two consensus protocols: Proof-of-Context (PoC) and Proof-of-Equivalence (PoE). PoC employs users’ context to add data on Mneme. PoE is executed periodically to summarize data in order to produce equivalent blocks that require less storage. We analyze the security of Mneme and justify the ability of PoC and PoE to guarantee the
characteristics of distributed ledgers: persistence and liveness. Furthermore, we analyze potential attacks from malicious users and prove that the probability of a successful attack is inversely proportional to the square of the number of mobile users who maintain Mneme.