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Percolation model of insider threats to assess the optimum number of rules

November 5, 2015
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Journal Article
Author:
Jeremy Kepner
…
Published in:
Environ. Syst. Decis., Vol. 35, 2015, pp. 504-10.
Topic:
modeling
R&D area:
R&D group:

Summary

Rules, regulations, and policies are the basis of civilized society and are used to coordinate the activities of individuals who have a variety of goals and purposes. History has taught that over-regulation (too many rules) makes it difficult to compete and under-regulation (too few rules) can lead to crisis. This implies an optimal number of rules that avoids these two extremes. Rules create boundaries that define the latitude at which an individual has to perform their activities. This paper creates a Toy Model of a work environment and examines it with respect to the latitude provided to a normal individual and the latitude provided to an insider threat. Simulations with the Toy Model illustrate four regimes with respect to an insider threat: under-regulated, possibly optimal, tipping point, and over-regulated. These regimes depend upon the number of rules (N) and the minimum latitude (Lmin) required by a normal individual to carry out their activities. The Toy Model is then mapped onto the standard 1D Percolation Model from theoretical physics, and the same behavior is observed. This allows the Toy Model to be generalized to a wide array of more complex models that have been well studied by the theoretical physics community and also show the same behavior. Finally, by estimating N and Lmin, it should be possible to determine the regime of any particular environment.
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Summary

Rules, regulations, and policies are the basis of civilized society and are used to coordinate the activities of individuals who have a variety of goals and purposes. History has taught that over-regulation (too many rules) makes it difficult to compete and under-regulation (too few rules) can lead to crisis. This...

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Percolation model of insider threats to assess the optimum number of rules

Domain mismatch compensation for speaker recognition using a library of whiteners

November 1, 2015
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Journal Article
Author:
Elliot Singer
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Published in:
IEEE Signal Process. Lett., Vol. 22, No. 11, November 2015, pp. 2000-2003.
Topic:
speaker recognition
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Summary

The development of the i-vector framework for generating low dimensional representations of speech utterances has led to considerable improvements in speaker recognition performance. Although these gains have been achieved in periodic National Institute of Standards and Technology (NIST) evaluations, the problem of domain mismatch, where the system development data and the application data are collected from different sources, remains a challenging one. The impact of domain mismatch was a focus of the Johns Hopkins University (JHU) 2013 speaker recognition workshop, where a domain adaptation challenge (DAC13) corpus was created to address this problem. This paper proposes an approach to domain mismatch compensation for applications where in-domain development data is assumed to be unavailable. The method is based on a generalization of data whitening used in association with i-vector length normalization and utilizes a library of whitening transforms trained at system development time using strictly out-of-domain data. The approach is evaluated on the 2013 domain adaptation challenge task and is shown to compare favorably to in-domain conventional whitening and to nuisance attribute projection (NAP) inter-dataset variability compensation.
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Summary

The development of the i-vector framework for generating low dimensional representations of speech utterances has led to considerable improvements in speaker recognition performance. Although these gains have been achieved in periodic National Institute of Standards and Technology (NIST) evaluations, the problem of domain mismatch, where the system development data and...

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Domain mismatch compensation for speaker recognition using a library of whiteners

Unlocking user-centered design methods for building cyber security visualizations(3.93 MB)

October 26, 2015
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Conference Paper
Author:
Sean P. McKenna
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Published in:
Proceedings of 2015 IEEE Symposium on Visualization for Cyber Security (VizSec)
Topic:
visualization
R&D area:
R&D group:

Summary

User-centered design can aid visualization designers to build better, more practical tools that meet the needs of cyber security users. In this paper, we discuss three design methods and illustrate how each method informed two real-world cyber security visualization projects which resulted in successful deployments to users.
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Summary

User-centered design can aid visualization designers to build better, more practical tools that meet the needs of cyber security users. In this paper, we discuss three design methods and illustrate how each method informed two real-world cyber security visualization projects which resulted in successful deployments to users.

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Unlocking user-centered design methods for building cyber security visualizations

VAST Challenge 2015: Mayhem at Dinofun World(757.94 KB)

October 25, 2015
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Conference Paper
Author:
Mark Whiting
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Published in:
Proceedings of 2015 IEEE Conference on Visual Analytics Science and Technology (VAST)
Topic:
visualization
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Summary

A fictitious amusement park and a larger-than-life hometown football hero provided participants in the VAST Challenge 2015 with an engaging yet complex storyline and setting in which to analyze movement and communication patterns.
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Summary

A fictitious amusement park and a larger-than-life hometown football hero provided participants in the VAST Challenge 2015 with an engaging yet complex storyline and setting in which to analyze movement and communication patterns.

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VAST Challenge 2015: Mayhem at Dinofun World

The evolution to modern phased array architectures

October 20, 2015
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Journal Article
Author:
Jeffrey S. Herd
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Published in:
Proceedings of the IEEE, Vol. 104, No. 3, March 2016, pp. 519-529.
Topic:
radar
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Summary

Phased array technology has been evolving steadily with advances in solid-state microwave integrated circuits, analysis and design tools, and reliable fabrication practices. With significant government investments, the technologies have matured to a point where phased arrays are widely used in military systems. Next-generation phased arrays will employ high levels of digitization, which enables a wide range of improvements in capability and performance. Digital arrays leverage the rapid commercial evolution of digital processor technology. The cost of phased arrays can be minimized by utilizing high-volume commercial microwave manufacturing and packaging techniques. Dramatic cost reductions are achieved by employing a tile array architecture, which greatly reduces the number of printed circuit boards and connectors in the array.
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Summary

Phased array technology has been evolving steadily with advances in solid-state microwave integrated circuits, analysis and design tools, and reliable fabrication practices. With significant government investments, the technologies have matured to a point where phased arrays are widely used in military systems. Next-generation phased arrays will employ high levels of...

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The evolution to modern phased array architectures

Mission assurance as a function of scale

October 14, 2015
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Conference Paper
Author:
Pierre C. Trepagnier
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Published in:
36th NATO Information Systems Technology Panel, 14-16 October 2015.
Topic:
systems analysis
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Summary

Since all Department of Defense (DoD) missions depend on cyber assets and capabilities, a dynamic and accurate cyber dependency analysis is a critical component of mission assurance. Mission analysis aims to identify hosts and applications that are "mission critical" so they can be monitored, and resources preferentially allocated to mitigate risks. For missions limited in duration and scale (tactical missions), dependency analysis is possible to conceptualize in principle, although currently difficult to realize in practice. However, for missions of long duration and large scale (strategic missions), the situation is murkier. In particular, cyber researchers struggle to find technologies that will scale up to large numbers of hosts and applications, since a typical strategic DoD mission might expect to leverage a large enterprise network. In this position paper, we argue that the difficulty is fundamental: as the mission timescale becomes longer and longer, and the number of hosts associated with the mission becomes larger and larger, the mission encompasses the entire network, and mission defense becomes indistinguishable from classic network defense. Concepts generally associated with mission assurance, such as fight-through, are not well suited to these long timescales and large networks. This train of thought leads us to reconsider the concept of "scalability" as it applies to mission assurance, and suggest that a hierarchical abstraction approach be applied. Large-scale, long duration mission assurance may be treated as the interaction of many small-scale, short duration tactical missions.
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Summary

Since all Department of Defense (DoD) missions depend on cyber assets and capabilities, a dynamic and accurate cyber dependency analysis is a critical component of mission assurance. Mission analysis aims to identify hosts and applications that are "mission critical" so they can be monitored, and resources preferentially allocated to mitigate...

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Mission assurance as a function of scale

Control jujutsu: on the weaknesses of fine-grained control flow integrity

October 12, 2015
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Conference Paper
Author:
Hamed Okhravi
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Published in:
22nd ACM Conf. on Computer and Communications Security, 12-16 October 2015.
Topic:
systems analysis
R&D area:
R&D group:

Summary

Control flow integrity (CFI) has been proposed as an approach to defend against control-hijacking memory corruption attacks. CFI works by assigning tags to indirect branch targets statically and checking them at runtime. Coarse-grained enforcements of CFI that use a small number of tags to improve the performance overhead have been shown to be ineffective. As a result, a number of recent efforts have focused on fine-grained enforcement of CFI as it was originally proposed. In this work, we show that even a finegrained form of CFI with unlimited number of tags and a shadow stack (to check calls and returns) is ineffective in protecting against malicious attacks. We show that many popular code bases such as Apache and Nginx use coding practices that create flexibility in their intended control flow graph (CFG) even when a strong static analyzer is used to construct the CFG. These flexibilities allow an attacker to gain control of the execution while strictly adhering to a fine-grained CFI. We then construct two proof-of-concept exploits that attack an unlimited tag CFI system with a shadow stack. We also evaluate the difficulties of generating a precise CFG using scalable static analysis for real-world applications. Finally, we perform an analysis on a number of popular applications that highlights the availability of such attacks.
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Summary

Control flow integrity (CFI) has been proposed as an approach to defend against control-hijacking memory corruption attacks. CFI works by assigning tags to indirect branch targets statically and checking them at runtime. Coarse-grained enforcements of CFI that use a small number of tags to improve the performance overhead have been...

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Control jujutsu: on the weaknesses of fine-grained control flow integrity

Timely rerandomization for mitigating memory disclosures

October 12, 2015
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Conference Paper
Author:
David Bigelow
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Published in:
22nd ACM Conf. on Computer and Communications Security, 12-16 October 2015.
Topic:
systems architecture
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Summary

Address Space Layout Randomization (ASLR) can increase the cost of exploiting memory corruption vulnerabilities. One major weakness of ASLR is that it assumes the secrecy of memory addresses and is thus ineffective in the face of memory disclosure vulnerabilities. Even fine-grained variants of ASLR are shown to be ineffective against memory disclosures. In this paper we present an approach that synchronizes randomization with potential runtime disclosure. By applying rerandomization to the memory layout of a process every time it generates an output, our approach renders disclosures stale by the time they can be used by attackers to hijack control flow. We have developed a fully functioning prototype for x86_64 C programs by extending the Linux kernel, GCC, and the libc dynamic linker. The prototype operates on C source code and recompiles programs with a set of augmented information required to track pointer locations and support runtime rerandomization. Using this augmented information we dynamically relocate code segments and update code pointer values during runtime. Our evaluation on the SPEC CPU2006 benchmark, along with other applications, show that our technique incurs a very low performance overhead (2.1% on average).
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Summary

Address Space Layout Randomization (ASLR) can increase the cost of exploiting memory corruption vulnerabilities. One major weakness of ASLR is that it assumes the secrecy of memory addresses and is thus ineffective in the face of memory disclosure vulnerabilities. Even fine-grained variants of ASLR are shown to be ineffective against...

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Timely rerandomization for mitigating memory disclosures

Enhancing the far-ultraviolet sensitivity of silicon complementary metal oxide semiconductor imaging arrays

October 1, 2015
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Journal Article
Author:
Kurt D. Retherford
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Published in:
J. Astron. Telesc. Instrum. Syst., Vol. 1, No. 4, Oct. - Dec. 2015, 046001.
Topic:
semiconductor (CMOS)
R&D area:
R&D group:

Summary

We report our progress toward optimizing backside-illuminated silicon P-type intrinsic N-type complementary metal oxide semiconductor devices developed by Teledyne Imaging Sensors (TIS) for far-ultraviolet (UV) planetary science applications. This project was motivated by initial measurements at Southwest Research Institute of the far-UV responsivity of backside-illuminated silicon PIN photodiode test structures, which revealed a promising QE in the 100 to 200 nm range. Our effort to advance the capabilities of thinned silicon wafers capitalizes on recent innovations in molecular beam epitaxy (MBE) doping processes. Key achievements to date include the following: (1) representative silicon test wafers were fabricated by TIS, and set up for MBE processing at MIT Lincoln Laboratory; (2) preliminary far-UV detector QE simulation runs were completed to aid MBE layer design; (3) detector fabrication was completed through the pre-MBE step; and (4) initial testing of the MBE doping process was performed on monitoring wafers, with detailed quality assessments.
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Summary

We report our progress toward optimizing backside-illuminated silicon P-type intrinsic N-type complementary metal oxide semiconductor devices developed by Teledyne Imaging Sensors (TIS) for far-ultraviolet (UV) planetary science applications. This project was motivated by initial measurements at Southwest Research Institute of the far-UV responsivity of backside-illuminated silicon PIN photodiode test structures...

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Enhancing the far-ultraviolet sensitivity of silicon complementary metal oxide semiconductor imaging arrays

Enhanced signal processing algorithms for the ASR-9 Weather Systems Processor

October 1, 2015
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Journal Article
Author:
John Y. Cho
Published in:
J. Atmos. Ocean. Technol., Vol. 32, No. 10, October 2015, pp. 1847-59.
Topic:
algorithms
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R&D group:

Summary

New signal processing algorithms for the Airport Surveillance Radar-9 (ASR-9) Weather Systems Processor (WSP) are introduced. The Moving Clutter Spectral Processing for Uneven-Sampled Data with Dealiasing (MCSPUDD) algorithm suite removes isolated moving clutter targets and corrects aliased velocity values on a per-range-gate basis. The spectral differencing technique is applied to the low- and high-beam data to produce a dual-beam velocity estimate that is more accurate than the current autocorrelation-lag-1-based approach. Comparisons with Terminal Doppler Weather Radar (TDWR) data show that estimate errors are reduced by 8%, 15%, and 15% for the low-, high-, and dual-beam velocities, respectively.
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Summary

New signal processing algorithms for the Airport Surveillance Radar-9 (ASR-9) Weather Systems Processor (WSP) are introduced. The Moving Clutter Spectral Processing for Uneven-Sampled Data with Dealiasing (MCSPUDD) algorithm suite removes isolated moving clutter targets and corrects aliased velocity values on a per-range-gate basis. The spectral differencing technique is applied to...

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Enhanced signal processing algorithms for the ASR-9 Weather Systems Processor
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