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Events for June 12, 2017

  • PhD Defense - Simon Woo

    Mon, Jun 12, 2017 @ 09:00 AM - 11:00 AM

    Computer Science

    University Calendar

    PhD Candidate: Simon Woo
    Date: June 12, 2017
    Time: 9:00am-11:00am
    Location: SAL 322
    Jelena Mirkovic (Adviser)

    Ron Artstein

    Kevin Knight

    Elsi Kaiser (outside member)


    Textual passwords are widely used for user authentication, but they are often difficult for a user to recall, and easily cracked by automated programs, and heavily re-used. Weak or reused passwords are guilty for many contemporary security breaches. Hence, it is critical to study both how users choose and reuse passwords, and the reasons that they adopt unsafe practices. In this thesis, I first examine the reasons why people create weak passwords and reuse these over multiple accounts. My research complements the body of existing works by studying the semantic structure, strength and reuse of real passwords, as well as conscious and unconscious causes of unsafe practices, using a test group population of 50 participants. Significant reuse and weak passwords clearly demonstrate the need for alternative authentication methods that are more memorable, secure, and less reused. My next three key thesis topics focus on developing novel authentication mechanisms that can directly improve current approaches. The first approach, "Life-Experience Passwords (LEPs)." uses a person's prior life experience as information to generate more memorable and secure authentication questions. We show that LEPs significantly raise the level of memorability and security compared to existing passwords and security questions. My second approach constructs more memorable and more secure passphrases through the novel use of mnemonics - multi-letter abbreviations of passphrases (MNPass), made of the first letters of each word in a passphrase. I apply mnemonics when generating and authenticating passphrases and show that the mnemonics-based approach improved recall compared to randomly generated passphrases and enhanced strength compared to user-selected passphrases. My last work explores password creation with semantic feedback (GuidedPass). I analyze user-input passwords and provide real-time, specific suggestions for improvement based on their existing semantic structure. GuidedPass passwords are 10^4 to 10^7 times stronger and as memorable as user initial passwords. GuidedPass passwords are also 100 times stronger and 1.2 times more memorable than passwords created with only password-meter feedback.

    Simon Woo is a Ph.D. candidate advised by Prof. Jelena Mirkovic. His current research focuses on improving user authentication, and understanding human factors in cybersecurity to better design secure systems.

    Location: 322

    Audiences: Everyone Is Invited

    Contact: Lizsl De Leon

  • MHI CommNetS seminar

    Mon, Jun 12, 2017 @ 02:00 PM - 03:00 PM

    Ming Hsieh Department of Electrical and Computer Engineering

    Conferences, Lectures, & Seminars

    Speaker: Dr. Costas A. Courcoubetis, Singapore University of Technology and Design

    Talk Title: Drivers, Riders and Service Providers: The impact of the sharing economy on Mobility

    Series: CommNetS

    Abstract: Joint work with S. Benjaafar and H. Bernhard.
    Ride sharing, the practice of sharing a car such that more than one person travels in the car during a journey, is often heralded as a more sustainable alternative of private transportation. It is widely believed that ride sharing through sharing economy platforms will significantly reduce congestion in populated urban areas. We introduce a model in which individuals may share rides for a certain fee, paid from the rider(s) to the driver through a ride sharing platform. Collective decision making is modelled as an anonymous non-atomic game with a finite set of strategies and payoff functions affine in the individuals' types that include their utility for using private transportation and their income. We demonstrate that equilibria in this game may be represented as convex partitions of the two dimensional type space and are unique for almost all parameter combinations. With this model we study how congestion and ownership are affected through the introduction of a ride sharing platform to a population of given characteristics. In particular, we examine whether the potential reduction in congestion widely expected is actually attainable once monetary incentives are introduced that affect both the behaviour of users and the price choices of the platform.
    We find that when car costs are low, casual ride sharing (P2P) will dominate the ride sharing market. When car costs are high, professional ride sharing (B2C) will dominate. Focusing on a monopolist revenue maximizing platform we encounter some paradoxical phenomena: For example, increasing car ownership costs as a measure to curb traffic volume might yield counter-intuitive outcomes: an increase in traffic volume, ownership and platform revenue coupled with a decrease in welfare. Comparing a revenue - with a welfare-maximizing platform we find that when cars are cheap the two platform objectives may be aligned. When cars are expensive, a revenue maximizing platform tends to induce an equilibrium with strictly worse welfare and strictly higher congestion compared to the welfare optimum. This suggests that in such a setting, a monopolist platform would need to be regulated more strictly to avoid socially undesirable outcomes.

    Biography: Prof. Costas A Courcoubetis was born in Athens, Greece and received his Diploma (1977) from the National Technical University of Athens, Greece, in Electrical and Mechanical Engineering, his MS (1980) and PhD (1982) from the University of California, Berkeley, in Electrical Engineering and Computer Science. He was MTS at the Mathematics Research Center, Bell Laboratories, Professor in the Computer Science Department at the University of Crete, Professor in the Department of Informatics at the Athens University of Economics and Business, and since 2013 Professor in the ESD Pillar, Singapore University of Technology and Design where he heads the Initiative for the Sharing Economy and co-directs the new ST-SUTD Center for Smart Systems. His current research interests are economics and performance analysis of networks and internet technologies, sharing economy, regulation policy, smart grids and energy systems, resource sharing and auctions. Besides leading a large number of research projects in these areas he has also published over 100 papers in scientific journals and conferences. He is co-author with Richard Weber of "Pricing Communication Networks: Economics, Technology and Modeling" (Wiley, 2003).

    Host: Prof. Insoon Yang

    Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248

    Audiences: Everyone Is Invited

    Contact: Annie Yu