A composite-metric based path selection technique for the Tor anonymity network

Path selection algorithm which considers bandwidth, reliability, propagation delay.Double the performance when compared to the default path selection used in Tor.Paths created to the average geo-location, hence more stable paths and less delay.No change required to current Tor network, only interested clients should update. The Tor anonymous network has become quite popular with regular users on the Internet. In the Tor network, an anonymous path is created by selecting three relays through which the connection is redirected. Nevertheless, as the number of Tor users has increased substantially in recent years, the algorithm with which the relays are selected affects the performance provided by the Tor network. More importantly as the performance suffers, users will leave the network, resulting in a lower anonymity set and in turn lower security provided by Tor network. In this paper, we proposed an algorithm for improving performance and security of the Tor network, by employing a combination of different metrics in the process of the path selection between the source and destination node. These metrics are bandwidth and uptime of relays as node conditions and delays between the relays as a path condition. Through a number of experiments we show that we could double the performance observed by end users when using the proposed technique as opposed to the current Tor path selection algorithm. More importantly, the proposed technique only requires a software upgrade on the client side, and other Tor nodes do not need to be modified.

[1]  Nicholas Hopper,et al.  How much anonymity does network latency leak? , 2007, TSEC.

[2]  Micah Adler,et al.  Defending anonymous communications against passive logging attacks , 2003, 2003 Symposium on Security and Privacy, 2003..

[3]  Andriy Panchenko,et al.  Path Selection Metrics for Performance-Improved Onion Routing , 2009, 2009 Ninth Annual International Symposium on Applications and the Internet.

[4]  John R. Douceur,et al.  The Sybil Attack , 2002, IPTPS.

[5]  Nadia Heninger,et al.  Torchestra: reducing interactive traffic delays over tor , 2012, WPES '12.

[6]  Micah Sherr,et al.  An Empirical Evaluation of Relay Selection in Tor , 2013, NDSS.

[7]  Tao Wang,et al.  Congestion-Aware Path Selection for Tor , 2012, Financial Cryptography.

[8]  Christopher Soghoian Enforced Community Standards for Research on Users of the Tor Anonymity Network , 2011, Financial Cryptography Workshops.

[9]  Ian Goldberg,et al.  PCTCP: per-circuit TCP-over-IPsec transport for anonymous communication overlay networks , 2013, CCS.

[10]  Paul F. Syverson,et al.  More Anonymous Onion Routing Through Trust , 2009, 2009 22nd IEEE Computer Security Foundations Symposium.

[11]  Micah Sherr,et al.  Scalable Link-Based Relay Selection for Anonymous Routing , 2009, Privacy Enhancing Technologies.

[12]  Nick Mathewson,et al.  Trust-based anonymous communication: adversary models and routing algorithms , 2011, CCS '11.

[13]  Prateek Mittal,et al.  Re3: relay reliability reputation for anonymity systems , 2014, AsiaCCS.

[14]  Dirk Grunwald,et al.  Shining Light in Dark Places: Understanding the Tor Network , 2008, Privacy Enhancing Technologies.

[15]  Sugih Jamin,et al.  Inet-3.0: Internet Topology Generator , 2002 .

[16]  Kevin Jeffay,et al.  Tracking the evolution of Web traffic: 1995-2003 , 2003, 11th IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer Telecommunications Systems, 2003. MASCOTS 2003..

[17]  Nick Feamster,et al.  Location diversity in anonymity networks , 2004, WPES '04.

[18]  Paul F. Syverson,et al.  As-awareness in Tor path selection , 2009, CCS.

[19]  Vladimiro Sassone,et al.  Trust in Anonymity Networks , 2010, CONCUR.

[20]  Micah Sherr,et al.  The design and implementation of the A3 application-aware anonymity platform , 2014, Comput. Networks.

[21]  Micah Sherr,et al.  ExperimenTor: A Testbed for Safe and Realistic Tor Experimentation , 2011, CSET.

[22]  Nikita Borisov,et al.  A Tune-up for Tor: Improving Security and Performance in the Tor Network , 2008, NDSS.

[23]  Harsha V. Madhyastha,et al.  LASTor: A Low-Latency AS-Aware Tor Client , 2014, IEEE/ACM Trans. Netw..

[24]  Bart Preneel,et al.  Towards Measuring Anonymity , 2002, Privacy Enhancing Technologies.

[25]  Ian Goldberg,et al.  DefenestraTor: Throwing Out Windows in Tor , 2011, PETS.

[26]  Nick Mathewson,et al.  Tor: The Second-Generation Onion Router , 2004, USENIX Security Symposium.

[27]  Micah Sherr,et al.  Exploring the potential benefits of expanded rate limiting in Tor: slow and steady wins the race with Tortoise , 2011, ACSAC '11.

[28]  Thomas Engel,et al.  Improving performance and anonymity in the Tor network , 2012, 2012 IEEE 31st International Performance Computing and Communications Conference (IPCCC).