Evaluating routing algorithms for "bleep", an iPhone based mobile ad hoc network for major public events

Bachelor's thesis of spring/summer semester 2024 (6th study plan semester)

This bachelor’s thesis deals with the evaluation of efficient peer-to-peer routing methods for mobile ad-hoc networks (MANET) using Bluetooth Low Energy (BLE) on iOS devices. The focus is on the question of how telecommunication can be enabled despite failures or overloads of the mobile network infrastructure, such as at large events. Existing applications were analyzed, including Bluetooth Mesh, Serval, FireChat, Berty, Briar, and Bridgefy. It became apparent that they were either discontinued or did not meet the central requirements of such a telecommunication service. Additionally, several routing methods were examined, categorized, and finally two were selected for comparison: the forwarding-based Disconnected Transitive Communication (DTC) and the replication-based Binary Spray and Wait (BSaW) algorithm. In the practical part of the thesis, the app bleep was developed from scratch. It demonstrates connectionless end-to-end message delivery to unicast addresses in a meshed, delay-tolerant MANET and implements both algorithms to test them and their energy efficiency under real conditions. However, it was found that the application could not achieve the desired functionality mainly due to limitations in the iOS Core Bluetooth framework. A theoretical comparison revealed that contrary to expectations, DTC does not enable more efficient routing than BSaW. This is due to a high number of required transmissions on the network access layer. The results also suggest that Bluetooth Mesh provides a better foundation for the described telecommunication service.