Blockchain-based distributed reputation model for ensuring trust in mobile adhoc networks

Mobile ad-hoc networks also known as MANETs have been in global use for numerous applications which are not possible with fixed network topologies. The distributed operation and dynamic topology have encouraged MANETs to be applied for establishing communication in unstable environments. MANET's dynamic topology and mobility have been very advantageous in the fields of military and disaster management. These dynamic characteristics of a MANET also create a major challenge in managing trust between the mobile nodes. Managing the trustworthiness of information that a node provides to the rest of the MANET is very crucial as misinformation spread can lead to erroneous decision making. Although previous studies have been carried out on trust management in MANETs using price-based and reputation systems, the potential of a globally distributed system has not been utilized practically. Therefore, these systems address the trust management issue within a boundary of a single MANET. Above mentioned systems should be re-evaluated when a node from another MANET joins a new MANET as the reputations of the node in the previous MANET cannot be imported to the new MANET. Lack of a possible solution for this gap may result in misinformation spreading by a malicious node before other nodes determine its reputation, which could be very dangerous in sensitive environments. Therefore, a globally distributed reputation model is a timely need in mobile ad-hoc networking. Blockchain technology is one of the most suitable technologies in present for its immutable and distributed properties to build robust systems. Blockchain is a distributed ledger, that has the ability to store feedback from mobile nodes about the accuracy of information provided by other nodes. A trust factor for each node can be calculated using these feedbacks. A mobile node can then decide whether to trust information, based on nodes’ trust factors. Adopting a development-oriented research methodology, a blockchain based reputation model prototype has been implemented and validated within the study.