Hardware technologies have made steady progress in miniaturization of sensors and computing/communication devices, which has driven a trend towards pervasive computing, which is a way to let computing devices directly interact with the physical world to monitor the natural environment, to provide building safety, and so on. In order to make pervasive computing a reality, it is critical to secure the underlying networked embedded systems, because these systems may collect important environment data upon which time-sensitive decisions are dependent.

Unfortunately, many of networked embedded systems, e.g. wireless and wired sensor networks, RFID infrastructure, wireless mesh networks, have components or links that are openly exposed to potential adversaries and hence are under constant security threats such as node capture, denial of service, and intrusion, among others. To make the matters worse, many networked embedded systems have much more constrained resources such as storage, bandwidth, computing power and energy than computers used in non-embedded applications, e.g. desktop machines and servers. Sophisticated computer security schemes developed over the last few decades are often infeasible on networked embedded systems, at least not in their original forms.

The research team of this project develops a multi-grade monitoring scheme, supported by a new programming interface, in which low-cost monitoring activities are deployed in normal mode of operation of the systems to detect suspicious symptoms which are possibly, although not necessarily, caused by security threats. This effort will lead to much more effective, yet affordable, security monitoring and defense on networked embedded systems.

Modeling complex real world problems in the national and homeland security domains require multi-disciplinary thinking and utilize multiple analytical approaches to represent massive numbers of entities, their behaviors, and the emergent interactions among them. As such, the traditional approach to building comprehensive, requirements-driven simulations does not work for such problems. This project uses a Society-based Approach to Integration using a ?shared but self-managed? paradigm, wherein, autonomous members collaborate in a society while sharing only a part of their knowledge. Component simulations self-assemble into realistic synthetic environments. The self-assembly of simulations is achieved through a domain-specific ontology, simulation specifications, and semantic matching between diverse members. New members join an existing society or an existing member modify its interaction needs without requiring the society to reconfigure. Using knowledge discovery, each member determines what aspects of entities in the society to interact with. In this way, a society is automatically configured into a synthetic environment. Broader impacts of this project include: creation and deployment of large scale synthetic environments by bridging new and existing models and simulations from diverse disciplines; leverage knowledge generated by the wider DDDAS community in creating complex synthetic environments at scales and diversity much greater than the state-of-the-art; facilitate rapid integration across diverse systems and paradigms, such as, discrete event simulations with agent based simulations, in a semantically consistent manner; and develop open source technology that will benefit the community at large with broader application to simulation based engineering, education, and decision analytics.

This project applies recent techniques in transactional computing to the problem of preventing unwanted declassification of secure information. Regulating the nature and amount of information that is declassified for complex software system is difficult; even when leaks are identified, suitably repairing the computation is usually not possible. The project develops ideas inspired from language-centric transactional computing to support information flow security by encapsulating critical regions that (a) either cannot be analyzed effectively statically or (b) declassify some set of confidential data. Isolation and atomicity properties of transactional regions ensure the approach is safe even in a multi-threaded environment. The technical issues associated with controlled declassification are examined from an entirely new perspective—rather than attempting to prevent statically any leaks from occurring, this research explores approaches that dynamically monitor when leaks occur, transparently reverting program state to an earlier safe context when leaks are identified. This security model encapsulates untrusted operations and library functions within monitored regions, allowing only information explicitly marked as declassified to escape the region scope. As regions run in isolation, they ensure that they can not be influenced by non-monitored code, nor can they influence its outcome. The monitoring infrastructure leverages transactional mechanisms to track memory use, and restore program state when declassification violations are detected. The broader impacts are significant. Information flow and declassification are critical problems to cyber-infrastructure, homeland security, and commercial interests. Techniques that provide scalable, transparent, and effective solutions to this problem are of immediate benefit to current government and business initiatives.

Created by the NW3C and CERT, and hosted by the Purdue University College of Technology, these workshops bring together members of the business, information technology, and law enforcement communities to initiate dialogue on computer security issues. Working together, participants identify the barriers to effective cooperation and investigate the ways to overcome those barriers.

In groups, participants define computer-related incidents, learn appropriate levels of response, and share effective solutions for dealing with computer incidents and crimes. Starting in single community teams (i.e., business, information technology, law enforcement), they analyze sample incidents. Then, teams reform into cross-community teams to simulate a task force and make recommendations about how to proceed. Discussion documents guide attendees through the process, with checklists for each professional role.

We study the minimum period of the Bell numbers, which arise in combinatorics, modulo a prime. It is shown that this period is probably always equal to its maximum possible value. Interesting new divisibility theorems are proved for possible prime divisors of the maximum possible period. The conclusion is that these numbers are not suitable for use as RSA public keys.