Performance measurements of tor hidden services in low-bandwidth access networks

Abstract

Being able to access and provide Internet services anonymously is an important mechanism to ensure freedom of speech in vast parts of the world. Offering location-hidden services on the Internet requires complex redirection protocols to obscure the locations and identities of communication partners. The anonymity system Tor supports such a protocol for providing and accessing TCP-based services anonymously. The complexity of the hidden service protocol results in significantly higher response times which is, however, a crucial barrier to user acceptance. This communication overhead becomes even more evident when using limited access networks like cellular phone networks. We provide comprehensive measurements and statistical analysis of the bootstrapping of client processes and different sub-steps of the Tor hidden service protocol under the influence of limited access networks. Thereby, we are able to identify bottlenecks for low-bandwidth access networks and to suggest improvements regarding these networks. © 2009 Springer Berlin Heidelberg.