Conference proceeding
Characterizing the Nature and Dynamics of Tor Exit Blocking
PROCEEDINGS OF THE 26TH USENIX SECURITY SYMPOSIUM (USENIX SECURITY '17), pp.325-341
01/01/2017
Abstract
Facing abusive traffic from the Tor anonymity network, online service providers discriminate against Tor users. In this study, we characterize not only the extent of such discrimination but also the nature of the undesired traffic originating from the Tor network-a task complicated by Tor's need to maintain user anonymity. We address this challenge by leveraging multiple independent data sources: email complaints sent to exit operators, commercial IP blacklists, webpage crawls via Tor, and privacy-sensitive measurements of our own Tor exit nodes. As part of our study, we also develop methods for classifying email complaints and an interactive crawler to find subtle forms of discrimination, and deploy our own exits in various configurations to understand which are prone to discrimination. We find that conservative exit policies are ineffective in preventing the blacklisting of exit relays. However, a majority of the attacks originating from Tor generate high traffic volume, suggesting the possibility of detection and prevention without violating Tor users' privacy.
Details
- Title: Subtitle
- Characterizing the Nature and Dynamics of Tor Exit Blocking
- Creators
- Rachee Singh - Univ Massachusetts, Amherst, MA 01003 USARishab Nithyanand - Stony Brook UniversitySadia Afroz - Univ Calif Berkeley, Berkeley, CA 94720 USAPaul Pearce - Univ Calif Berkeley, Berkeley, CA 94720 USAMichael Carl Tschantz - Int Comp Sci Inst, Berkeley, CA 94704 USAPhillipa Gill - Univ Massachusetts, Amherst, MA 01003 USAVern Paxson - Univ Calif Berkeley, Berkeley, CA 94720 USAUSENIX Association
- Resource Type
- Conference proceeding
- Publication Details
- PROCEEDINGS OF THE 26TH USENIX SECURITY SYMPOSIUM (USENIX SECURITY '17), pp.325-341
- Publisher
- Usenix Assoc
- Number of pages
- 17
- Grant note
- Open Technology Fund CNS-1237265; CNS-1518918; CNS-1406041; CNS-1350720; CNS-1518845; CNS-1422566 / NSF; National Science Foundation (NSF)
- Language
- English
- Date published
- 01/01/2017
- Academic Unit
- Computer Science; Public Policy Center (Archive); Center for Social Science Innovation
- Record Identifier
- 9984283572502771
Metrics
6 Record Views