This paper describes a specfication-based approach to detect exploitations of vulnerabilities in security-critical programs.  The approach utilizes security specifications that describe the intended behavior of programs and scans audit trails for operations that are in violation of the specifications…

Intrusion detection systems rely on a wide variety of observable data to distinguish between legitimate and illegitimate activities.  In this paper we study one such observable - sequences of system calls into the kernel of an operating system…

An attractive target for a computer system attacker is the router.  An attacker in control of a router can disrupt communication by dropping or misrouting packets passing through the router.  We present a protocol called Watchers that detects and reacts to routers that drop or misroute packets…

We\‘re looking into the fundamental problem of watermarking finite numeric sets. The wide area of applicability of the problem ranging from numeric database content to stock market analysis data, makes it especially intriguing when considering a generic solution and particularities of its various applications. Given a range of associated numeric constraints and assumptions we provide a generic solution and analyze associated attacks. We further present several problem applicability domains and relate it to some of our past and ongoing research in watermarking semistructures.

We present a Hierarchical Hybrid Network architecture for wireless networks.  In such a network, mobile nodes are hierarchically organized into groups.  Different groups can have different routing protocols.  Mobile nodes communicate with nodes outside their groups through the group agents.  The groups are highly autonomous.  This architecture is flexible and scalable.  We conduct experiments to compare the new architecture with Ad Hoc networks.  The new architecture has a more stable topology and higher throughput when the number of mobile nodes is large.  The objective of our research is to set up a survivable, secure mobile wireless network.

The development of inter-networked enterprises created a new computing environment in which information assurance is critical. The objective of this article is to investigate the information assurance needs of today

The design and operation of autonomous agents to assure information in ERP systems of inter-networked enterprises are investigated. A variable information assurance implementation model is proposed based on the AIMIS model, and a risk assessment procedure is applied. The protocols and models needed to support variable assurance are introduced and their performance is assessed. Experimentation shows the possibility to reduce the processing time of requests without decreasing the proportion of trusted requests, compared to a systematic total assurance approach.

Differential and linear cryptanalysis, two of the most important techniques in modern block cipher cryptanalysis, still lack a sound, generally-applicable analysis of their success probabilities. In this paper, we present an analytical calculation of the success probability of differential and linear cryptanalytic attacks. In addition to a formulation of the success probability, the analysis yields a formulation of the attacks’ data requirements as well, and it also finds the size of the aimed key information in differential cryptanalysis as one of the factors affecting the success probability. We also discuss the issue of key dependence in linear cryptanalysis, which can be a serious limitation for this technique of attack.

We construct several examples showing that two distinct pulses can have identical intensity autocorrelations and power spectra, from which we infer that retrieval methods based on these two datasets alone produce ambiguous solutions.