Alec Yasinsac

Computer forensics education

The application of science and education to computer-related crime forensics is still largely limited to law enforcement organizations. Building a suitable workforce development program could support the rapidly growing field of computer and network forensics.

Adaptive gossip protocols: Managing security and redundancy in dense ad hoc networks

Many ad hoc routing algorithms rely on broadcast flooding for location discovery or, more generally, for secure routing applications. Flooding is a robust algorithm but because of its extreme redundancy, it is impractical in dense networks. Indeed in large wireless networks, the use of flooding algorithms may lead to broadcast storms where the number of collisions is so large that it causes system failure. To prevent broadcast storms, many mechanisms that reduce redundant transmissions have been proposed that reduce retransmission overhead either deterministically or probabilistically. Gossip is a probabilistic algorithm in which packet retransmission is based on the outcome of coin tosses. The retransmission probability can be fixed, dynamic or adaptive. With dynamic gossip, local information is used to determine the retransmission probability. With adaptive gossip, the decision to relay is adjusted adaptively based on the outcome of coin tosses, the local network structure, and the local response to the flooding call. The goal of gossip is to minimize the number of retransmissions, while retaining the main benefits of flooding, e.g., universal coverage, minimal state retention, and path length preservation. In this paper we consider ways to reduce the number of redundant transmissions in flooding while guaranteeing security. We present several new gossip protocols that exploit local connectivity to adaptively correct propagation failures and protect against Byzantine attacks. A main contribution of this work is that we introduce a cell-grid approach that allows us to analytically prove performance and security protocol properties. The last two gossip protocols that we give are fully adaptive, i.e., they automatically correct all faults and guarantee delivery, the first such protocols to the best of our knowledge.

Ad hoc network security: peer identification and authentication using signal properties

As networking architectures grow and develop, the pace of security in these networks must keep pace. This paper is interested in identification and authentication in ad hoc networks, which are particularly susceptible to identity attacks, such as masquerading and malicious alias attacks. To mitigate these identity attacks, we propose to associate the message transmitter with a location and use this location information to reason about identity. There are several cooperative location schemes detailed in the literature, but because we cannot assume that a malicious party would cooperate in a location scheme, we propose to determine transmitter location by using the physical properties of the received signal.

Intellectual Property Protection in Additive Layer Manufacturing: Requirements for Secure Outsourcing

Additive Layer Manufacturing (ALM) is a new technology to produce 3D objects adding layer by layer. Agencies and companies like NASA, ESA, and SpaceX are exploring a broad range of application areas of ALM, which includes printing of device components, replacement parts, houses, and even food. They expect that this technology will greatly reduce production costs, manufacturing time, and necessary storage space. The broad variety of application areas and the high grade of computerization of this manufacturing process will inevitably make ALM an attractive target of various attacks. This research examines the problem of Intellectual Property (IP) protection in the case of outsourcing the ALM manufacturing process. We discuss the existing process and introduce a new model for the outsourcing of ALM-based production. For the proposed outsourcing model, focusing on IP protection, we present a risk assessment, specify requirements addressing mitigation of the identified risks, and outline approaches to implement the specified requirements. The fulfillment of the specified requirements will enable secure outsourcing of ALM production.

Accountable privacy

As the Internet has gained widespread use, and advanced technologies such as high-speed multi-media technologies and automated digital monitoring have become a reality, privacy is at the greatest risk of all time. At the same time, sophisticated threats from hackers, terrorists, thieves, and others that would abuse privacy highlight the need to find technologies that provide some accountability. However, the goals of accountability and of privacy appear to be in contradiction: accountability tends to be about determining which entities committed which actions, while privacy seeks to hide this information. In this paper, we discuss the apparent conflict that exists between privacy and accountability. We survey some of the issues in privacy and in accountability and highlight research directions for balancing the needs of both.

The Dynamics of Counting and Recounting Votes

The limitations of current paper- and electronic-based voting systems and recount procedures can undermine the credibility of public elections. A corroborative, redundant voting system that performs vote counts via independent mechanisms at the polling place could address these shortcomings. After discussing the strengths and weaknesses of electronic and paper ballots with respect to initial counts, we discuss auditing approaches to corroborate the initial reported results and propose protocols and procedures to strengthen the auditing mechanisms.

Analyzing Internet security protocols

In this paper, we show how a novel tool for analyzing classical cryptographic protocols can be used to model and analyze the more complex Internet security protocol families. We discuss the modifications that were necessary in the tool and how the tool illuminates flaws in the Transport Layer Security (TLS) protocol. We also show how a flaw carried over to TLS from the Secure Sockets Layer protocol (the predecessor of TLS) was illustrated using our tool.

A Risk Assessment Model for Voting Systems using Threat Trees and Monte Carlo Simulation

There continues to be a requirement for better models, tools, and techniques for conducting risk assessment of voting systems. We propose a model of risk and a technique for risk assessment, which builds on threat trees and Monte Carlo simulation. The goal is to provide a means of facilitating informed decisions regarding voting system security standards through a rational and parsimonious quantification of intuition or estimation of risk. Such a means should support an evaluation of trade-offs, sensitivity analysis, cost-benefit analysis, and estimation of residual risk of current and proposed voting systems, technologies and controls.

Automated Evaluation of Secure Route Discovery in MANET Protocols

Evaluation techniques to analyze security properties in ad hoc routing protocols generally rely on manual, non-exhaustive approaches. Non-exhaustive analysis techniques may conclude a protocol is secure, while in reality the protocol may contain an unapparent or subtle flaw. Using formalized exhaustive evaluation techniques to analyze security properties increases protocol confidence. In this paper, we offer an automated evaluation process to analyze security properties in the route discovery phase for on-demand source routing protocols. Using our automated security evaluation process, we are able to produce and analyze all topologies for a given network size. The individual network topologies are fed into the SPIN model checker to exhaustively evaluate protocol abstractions against an attacker attempting to corrupt the route discovery process.

Software issues in digital forensics

Whether we accept it or not, computer systems and the operating systems that direct them are at the heart of major forms of malicious activity. Criminals can use computers as the actual target of their malicious activity (stealing funds electronically from a bank) or use them to support the conduct of criminal activity in general (using a spreadsheet to track drug shipments). In either case, law enforcement needs the ability (when required) to collect evidence from such platforms in a reliable manner that preserves the fingerprints of criminal activity. Though such discussion touches on privacy issues and rules of legal veracity, we focus purely on technological support in this paper. Specifically, we examine and set forth principles of operating system (OS) design that may significantly increase the success of (future) forensic collection efforts. We lay out several OS design attributes that synergistically enhance forensics activities. Specifically, we pose the use of circuit encryption techniques to provide an additional layer of protection above hardware-enforced approaches. We conclude by providing an overarching framework to incorporate these enhancements within the context of OS design.