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[Colloquium] Recent Research Endeavors in Mobile Computing and Social Network Privacy

February 19, 2013

Watch Colloquium: 

M4V file (669 MB)

  • Date: Tuesday, February 19, 2013 
  • Time: 11:00 am — 11:50 am 
  • Place: Mechanical Engineering 218

Srikanth V. Krishnamurthy
Professor of Computer Science University of California, Riverside 

There has been an explosion both in smartphone sales and usage on one hand, and social network adoption on the other. Our work targets several directions in (a) exploiting the smartphone resources in an appropriate way for computing, information dissemination and sharing and storage and (b) making social networks more usable by providing fine grained privacy controls. In this talk, I present our recent work on mobile computing and privacy in online social networks. Specifically, I will describe (a) how one can go about building a distributed computing infrastructure using smartphones and (b) how one can provision fine-grained privacy controls with Twitter. Below, I provide a brief synopsis of the two projects.

Smartphone Cloud: Every night, a large number of idle smartphones are plugged into a power source for recharging the battery. Given the increasing computing capabilities of smartphones, these idle phones constitute a sizeable computing infrastructure. Therefore, for a large enterprise which supplies its employees with smartphones, we argue that a computing infrastructure that leverages idle smartphones being charged overnight is an energy-efficient and cost-effective alternative to running tasks on traditional server infrastructure. Building a cloud with smartphones presents a unique set of challenges that stem from heterogeneities in CPU Clock speed, variability in network bandwidth and low availability compared to servers. We address may of these challenges to build CWC — a distributed computing infrastructure using smartphones.

Twitsper: User privacy has been an increasingly growing concern in online social networks (OSNs). While most OSNs today provide some form of privacy controls so that their users can protect their shared content from other users, these controls are typically not sufficiently expressive and/or do not provide fine-grained protection of information. We consider the introduction of a new privacy control—group messaging on Twitter, with users having fine-grained control over who can see their messages. Specifically, we demonstrate that such a privacy control can be offered to users of Twitter today without having to wait for Twitter to make changes to its system. We do so by designing and implementing Twitsper, a wrapper around Twitter that enables private group communication among existing Twitter users while preserving Twitter’s commercial interests. Our design preserves the privacy of group information (i.e., who communicates with whom) both from the Twitsper server as well as from undesired users. Furthermore, our evaluation shows that our implementation of Twitsper imposes minimal server-side bandwidth requirements and incurs low client-side energy consumption.


Bio: Srikanth V. Krishnamurthy received his Ph.D degree in electrical and computer engineering from the University of California at San Diego in 1997. From 1998 to 2000, he was a Research Staff Scientist at the Information Sciences Laboratory, HRL Laboratories, LLC, Malibu, CA. Currently, he is a Professor of Computer Science at the University of California, Riverside. His research interests are in wireless networks, online social networks and network security. Dr. Krishnamurthy is the recipient of the NSF CAREER Award from ANI in 2003. He was the editor-in-chief for ACM MC2R from 2007 to 2009. He is a Fellow of the IEEE.