The SPARTA Lab is currently looking for self-motivated students seeking a Ph.D. in Computer Science and interested in pursuing research in topics related to computational social science, online privacy, and Internet measurement. Send an email to "rishab[-]nithyanand[at]uiowa[dot]edu" with the subject "you NEED to hire me!" if you're interested in working with us and have a demonstrably strong background in any of the following areas: computer networking, statistics, text analytics, or experiment design.

IPv6 Censorship

Eric Wustrow
Assistant Professor at University of Colorado - Boulder
Ian Martiny
PhD student at University of Colorado - Boulder
Rishab Nithyanand
Assistant Professor at University of Iowa
Hammas Bin Tanveer
PhD student at University of Iowa
Amir Houmansadr
Associate Professor at University of Massachusetts - Amherst
Jack Wampler
PhD student at University of Colorado - Boulder

What is Internet censorship?

Internet censorship is the act of filtering or reducing users’ access to information online. Such censorship can take many forms, from intimidation to the deployment of technical mechanisms that prevent network connections to content on the Internet. Our research focuses on characterizing the latter. We conduct measurements to better understand how such filtering is being performed by censors.

The emergence of IPv6

Deployment of the IPv6 standard has seen a rapid increase in the past decade with Google currently measuring 25-30% of their traffic being served over native IPv6 connections, 25% of all Internet-connected networks advertising IPv6 connectivity, and major mobile networks such as T-Mobile embracing the standard. Previous work has demonstrated that IPv6 deployment is rapidly increasing and that there is a need for IPv6-specific research – i.e., that research on the IPv4 Internet does not always carry over to the IPv6 Internet. Specifically, it is known that IPv6 topologies measured from control-plane data vary significantly from IPv4 topologies, IPv6 end-hosts are more vulnerable to compromise due to having more open ports than their IPv4 counterparts, the causes for IPv6 Internet background radiation are qualitatively different than the causes for IPv4 background radiation, and performance characteristics of IPv6 traffic have been worse than IPv4 due to difference in paths observed. These results suggest that IPv6 behaves differently than the IPv4 Internet in terms of routing, security, and performance.

How does IPv6 influence censorship and it’s circumvention?

What is lacking, however, is an understanding of how Internet information controls systems (i.e., censorship and traffic differentiation implementations) are impacted by the deployment of IPv6 and the role that IPv6 might play in the development of new censorship circumvention research and tools. This is especially important given the arms race nature of current censorship and circumvention research. Further, existing research has largely focused on the impact of IPv6 on endpoints and end-to-end path properties rather than middle boxes (i.e., where information control systems are deployed). In fact, our own preliminary work shows that the accessibility of information over IPv6 networks differs from IPv4 networks within the same region due to differences in how IPv6 information control systems are deployed at middle boxes. Accordingly, there is an urgent need for circumvention tool developers and researchers to measure how IPv6 deployments are impacting online information control systems and leverage IPv6 protocol and deployment features to augment existing and develop new circumvention tools. Not meeting this need at this time represents an important lost opportunity to gain an advantage in the existing developer vs. censor arms race and potential for ultimately ending the arms race via clean-slate circumvention tool design.

Goals of our research

Our long-term goal is to facilitate free and open communication over the Internet for populations subject to authoritarian governments. Our overall objective in the short-term is to develop measurement methodologies to track IPv6-specific information control deployments and develop new circumvention strategies which leverage features of the deployment and protocol.