Scalable Decentralized Privacy-Preserving Location Proximity
Examensarbete för masterexamen
Computer science – algorithms, languages and logic (MPALG), MSc
Bergersen, Alexander. M.
This report is the report of a Master Thesis carried out at Chalmers University of Technology by me, Alexander Bergersen. The aim of the Master Thesis was to introduce authentication into decentralized privacy-preserving location proximity without adversely hampering the scalability of such protocols further. This was done by creating two solutions that slightly modified the behavior of a location proximity protocol called “InnerCircle”. The first solution, called the Gossiping solution, tries to introduce authentication by having the base network be an unstructured distributed network where each client substitutes as an authentication authority for each of the clients connected to it, viewed as its neighbors. This solution assumes a majority honest network where each vote of authenticity from each neighbor carries equal weight. The second solution develops the first one by going in a different direction and uses an Identity Based Encryption system with distributed key generation as the basis. Instead of proving authentication it hides information from those not authorized to see it. However, even though the second solution is based on the first one, they are different enough that instead of the testing each solution and showing the progress, the solutions are compared as to which one is better and most fulfill the aim of not adversely affecting the performance of the underlying protocol, InnerCircle, the best. The test results are presented to the reader for each of three cases, baseline, first solution, second solution, in tables and the data is analyzed. This analysis showed that the Gossiping solution without the Identity Based Encryption will eventually always outperform the second solution, even if the Identity Based solution was developed with the goal of performing better than the Gossiping solution.
Data- och informationsvetenskap , Computer and Information Science