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Roya Ensafi Post Doc At Princeton

March 20, 2015

Roya Ensafi 
Department of Computer Science
Princeton University

How can we remotely measure Internet censorship around the world? Roya Ensafi, along with her PhD advisor Jed Crandall, has focused on developing practical side channels (a.k.a idle scans) for remotely measuring Internet censorship around the world. In particular, this can be done without requiring any kind of measurement platform or access to any of the machines that connectivity is tested to or from. Her idle scan technique, hybrid idle scan, enables researchers to test whether two arbitrary machines in the world are able to communicate via TCP/IP and, if not, in which direction packets are being dropped.

While at UNM, she applied the hybrid idle scan to the challenging problem of characterizing inconsistencies in the Great Firewall of China (GFW), the largest firewall in the world. This effort resolved many open questions about the GFW. She has successfully published papers in USENIX Security, PAM, PETS, and FOCI, that resulted in her passing her PhD defense with the Distinction Award for PhD dissertation in December 2014. Currently, she is a postdoc at Princeton University, collaborating with researchers from ICSI/Berkeley, Princeton, Washington, UNM, and The Tor Project to measure Internet censorship from a geographically and topologically diverse set of clients without requiring volunteers. 

The selected publications resulting from her dissertation include:

Analyzing the Great Firewall of China Over Space and Time
Roya Ensafi, Philipp Winter, Abdullah Mueen, Jedidiah R. Crandall
In Proc. of: Privacy Enhancing Technologies Symposium, 2015, PETs

Detecting Intentional Packet Drops on the Internet via TCP/IP Side Channels
Roya Ensafi, Jeffrey Knockel, Geoffrey Alexander, Jedidiah R. Crandall
In Proc. of: Passive and Active Measurements Conference, 2014, Springer

Idle Port Scanning and Non-interference Analysis of Network Protocol Stacks Using Model Checking
Roya Ensafi, Jong Chun Park, Deepak Kapur, Jedidiah R. Crandall
In Proc. of: USENIX Security Symposium, 2010, USENIX

Funding resulting from the work:

TWC: Small: Developing Advanced Digital Forensic Tools Based on Network Stack Side Channels. National Science Foundation.
TWC: Medium: Collaborative: Measurement and Analysis Techniques for Internet Freedom on IP and Social Networks. National Science Foundation. (joint project with Rice Univ.)