PPT-Toward Understanding Congestion in Tor

DCarea Anonymity Privacy and Security Seminar January 24 th 2014 Rob Jansen US Naval Research Laboratory Joint with John Geddes Chris Wacek Micah Sherr Paul Syverson. brPage 1br toward toward brPage 2br away from away from brPage 3br spectrum brPage 4br brPage 5br brPage 6br brPage 7br brPage 8br brPage 9br br Advanced Computer Networks: TCP Congestion Control. 1. Principles of Congestion Control. Congestion:. informally: “too many sources sending too much data too fast for the . network. to handle”. different from flow control!. Soprano         Alto   Leave, a- las,  this tor- ment-  ing, leave,   a- las, Tenor 1  Leave, a-  las, this   tor- ment-  \n    ing, tor-   ment-  \n  ing, leave, Te q ueMax Tor q ueMin Tor q ueMax Tor q ueMin Tor q ueMax Tor q Class 900Class 1500Class 2500Spiral Wound Gasket CGNPS (in.) q q q q q q 0.57012070120501000.757012070120701001101901101901101601.25110190 Aaron Johnson. 1 . . Chris Wacek. 2. . Rob Jansen. 1. Micah Sherr. 2. . Paul Syverson. 1. 1 . U.S. Naval Research Laboratory, Washington, DC. 2. Georgetown University, Washington, DC. MPI-SWS. Harald. . R. ä. cke. 1. Graph .  . Tree. .  . Approximation. Tree Approximation. Approximating a Graph by a Tree. Task:. Given an (undirected) graph G. . Compute a . decomposition tree . that is . Ihsan Ayyub Qazi. Background: Congestion Control. What is congestion?. A network state where the arrival rate exceeds the service rate. Throughput starts decreasing (due to packet losses). Delay increases fast (queues build up). Control. . (part II). EE 122, Fall 2013. Sylvia Ratnasamy. http://inst.eecs.berkeley.edu/~ee122. /. Material thanks to Ion . Stoica. , Scott . Shenker. , Jennifer Rexford, Nick . McKeown. , and many other colleagues. By: Conor Doherty and Kenneth Cabrera. Project Topics. What is the Tor Network?. How does Tor function?. How does Tor work to preserve anonymity?. What are the limits and weaknesses of Tor?. How much more secure is Tor than normal internet browsing. Qi (Gill) Wang. gillwang@udel.edu. CISC 856 – . TCP/IP, Fall 2012. Special thanks to:. Dr. Paul . Amer. Guna. . Ranjan. , Justin . Yackoski. , . Namratha. . Hundigopal. and . Preethi. . Natarajan. Source and Destination Prediction. Peter . Byerley. . Rindal. Sultan . Alanazi. Hafed . Alghamdi. Overview. What is Tor Network?. Motivation. How does Tor work?. Tor Protocol Weaknesses and security . 23. rd. USENIX Security Symposium. August 20. th. . 2014. Rob . Jansen. US Naval Research Laboratory. John Geddes University of Minnesota. Chris . Wacek. Georgetown University. Micah . Sherr. Georgetown University. Prateek Mittal . Femi Olumofin. Carmela Troncoso. Nikita Borisov. Ian Goldberg. Presented by Justin Chester. Background. Tor – Anonymous Routing. PIR: Private Information Retrieval . Related Work. PIR-Tor. What is Congestion Pricing?. Definition - . A financial means of influencing when people drive in certain areas. Primary Goal - . To reduce traffic congestion during periods of peak demand. Secondary Goal .