Keynote Speakers

18-Jan-2011: Assoc. Professor Heng Tao Shen

UQLIPS: A Real-time Near-duplicate Video Retrieval and Monitoring System

Recorded Keynote: Play the keynote

Abstract
The exponential growth of online videos, along with the increasing user involvements to video-related activities, has been observed as a constant phenomenon during last decade. User's time spent on video capturing, editing, uploading, searching and viewing has boosted to an unprecedented level. The massive publishing and sharing of videos has given rise to the existence of a already-large amount of near-duplicate content. This imposes urgent demands on near-duplicate video retrieval and monitoring as key roles in novel tasks such as video search, copyright protection, video recommendation, content tracking, redundancy removal, and many more. Driven by the strong significance, near-duplicate video retrieval and detection have recently attracted lots of attention.

19-Jan-2011: Professor Gene Tsudik

Usable Security: the case of user-aided pairing of wireless devices

Recorded Keynote: Play the keynote

Abstract
'Secure device pairing' is the process of bootstrapping a secure channel between two or more previously unassociated personal devices over a (usually wireless) human-imperceptible communication channel. Lack of prior security context and absence of common trust infrastructure open the door for so-called "Man-in-the-Middle" (or "Evil Twin") attacks. Mitigation of these attacks requires user involvement in the device pairing process. This research direction is both important and timely, since it considers usability in one of the few security-relevant settings that involves a wide range of users. Prior research yielded a number of interesting methods utilizing various auxiliary human-perceptible channels, e.g., visual, acoustic and tactile. These methods engage the user in authenticating information exchanged over human-imperceptible channels, thus countering attacks and forming the basis for secure device pairing.

This talk will begin by summarizing notable secure device pairing techniques, comparing and contrasting their advantages, shortcomings and limitations. Then, we present a comprehensive and comparative evaluation (based on both on usability and security) of these methods. Results identify methods best-suited for a given combination of devices and human abilities. Next, we consider the group setting where more than two unfamiliar devices need to be associated in order to set up a secure communication context. We then report on a usability study that compares several potential group pairing techniques. We conclude with some unresolved issues and potential avenues for future research.

20-Jan-2011: Professor Dexter Kozen

Computing with Capsules

Recorded Keynote: Play the keynote

Abstract
Capsules provide a clean algebraic representation of the state of a computation in higher-order functional and imperative languages with mutable bindings. Capsules play the same role as closures or heap- or stack-allocated environments but are much simpler. A capsule is essentially a syntactic representation of a finite coalgebra representing a regular closed lambda-coterm. In this talk I will describe a simple higher-order programming language with functional and imperative features, including mutable bindings, based on capsules. For computational purposes, all operations of interest are typable with simple types, yet the system is Turing complete. Recursive functions are represented directly as capsules, eliminating the need for unnatural fixpoint combinators that are untypable with simple types and impose a call-by-name discipline. I will give an operational semantics for the language and show that it correctly captures lexical scoping without any combinatorial constructs such as stacks, heaps, or closures.