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Dedicated vs. distributed: a study of mission survivability metrics

Published in:
MILCOM 2011, IEEE Military Communications Conf., 7-10 November 2011, pp. 1345-1350.

Summary

A traditional trade-off when designing a mission critical network is whether to deploy a small, dedicated network of highly reliable links (e.g. dedicated fiber) or a largescale, distributed network of less reliable links (e.g. a leased line over the Internet). In making this decision, metrics are needed that can express the reliability and security of these networks. Previous work on this topic has widely focused on two approaches: probabilistic modeling of network reliabilities and graph theoretic properties (e.g. minimum cutset). Reliability metrics do not quantify the robustness, the ability to tolerate multiple link failures, in a distributed network. For example, a fully redundant network and a single link can have the same overall source-destination reliability (0.9999), but they have very different robustness. Many proposed graph theoretic metrics are also not sufficient to capture network robustness. Two networks with identical metric values (e.g. minimum cutset) can have different resilience to link failures. More importantly, previous efforts have mainly focused on the source-destination connectivity and in many cases it is difficult to extend them to a general set of requirements. In this work, we study network-wide metrics to quantitatively compare the mission survivability of different network architectures when facing malicious cyber attacks. We define a metric called relative importance (RI), a robustness metric for mission critical networks, and show how it can be used to both evaluate mission survivability and make recommendations for its improvement. Additionally, our metric can be evaluated for an arbitrarily general set of mission requirements. Finally, we study the probabilistic and deterministic algorithms to quantify the RI metric and empirically evaluate it for sample networks.
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Summary

A traditional trade-off when designing a mission critical network is whether to deploy a small, dedicated network of highly reliable links (e.g. dedicated fiber) or a largescale, distributed network of less reliable links (e.g. a leased line over the Internet). In making this decision, metrics are needed that can express...

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Efficient transmission of DoD PKI certificates in tactical networks

Published in:
MILCOM 2011, IEEE Military Communications Conf., 7-10 November 2011, pp. 1739-1747.

Summary

The DoD vision of real-time information sharing and net-centric services available to warfighters at the tactical edge is challenged by low-bandwidth and high-latency tactical network links. Secured tactical applications require transmission of digital certificates that contribute a major portion of data in most secure sessions, which further increases response time for users and drains device power. In this paper we present a simple and practical approach to alleviating this problem. We develop a dictionary of data common across DoD PKI certificates to prime general-purpose data compression of certificates, resulting in a significant reduction (about 50%) of certificate sizes. This reduction in message size translates in to faster response times for the users. For example, a mutual authentication of a client and a server over the Iridium satellite link is expected to be sped up by as much as 3 sec. This approach can be added directly to tactical applications with minimal effort, or it can be deployed as part of an intercepting network proxy, completely transparent to applications.
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Summary

The DoD vision of real-time information sharing and net-centric services available to warfighters at the tactical edge is challenged by low-bandwidth and high-latency tactical network links. Secured tactical applications require transmission of digital certificates that contribute a major portion of data in most secure sessions, which further increases response time...

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Achieving cyber survivability in a contested environment using a cyber moving target

Published in:
High Frontier, Vol. 7, No. 3, May 2011, pp. 9-13.

Summary

We describe two components for achieving cyber survivability in a contested environment: an architectural component that provides heterogeneous computing platforms and an assessment technology that complements the architectural component by analyzing the threat space and triggering reorientation based on the evolving threat level. Together, these technologies provide a cyber moving target that dynamically changes the properties of the system to disadvantage the adversary and provide resiliency and survivability.
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Summary

We describe two components for achieving cyber survivability in a contested environment: an architectural component that provides heterogeneous computing platforms and an assessment technology that complements the architectural component by analyzing the threat space and triggering reorientation based on the evolving threat level. Together, these technologies provide a cyber moving...

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Creating a cyber moving target for critical infrastructure applications

Published in:
5th IFIP Int. Conf. on Critical Infrastructure Protection, ICCIP 2011, 19-21 March 2011.

Summary

Despite the significant amount of effort that often goes into securing critical infrastructure assets, many systems remain vulnerable to advanced, targeted cyber attacks. This paper describes the design and implementation of the Trusted Dynamic Logical Heterogeneity System (TALENT), a framework for live-migrating critical infrastructure applications across heterogeneous platforms. TALENT permits a running critical application to change its hardware platform and operating system, thus providing cyber survivability through platform diversity. TALENT uses containers (operating-system-level virtualization) and a portable checkpoint compiler to create a virtual execution environment and to migrate a running application across different platforms while preserving the state of the application (execution state, open files and network connections). TALENT is designed to support general applications written in the C programming language. By changing the platform on-the-fly, TALENT creates a cyber moving target and significantly raises the bar for a successful attack against a critical application. Experiments demonstrate that a complete migration can be completed within about one second.
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Summary

Despite the significant amount of effort that often goes into securing critical infrastructure assets, many systems remain vulnerable to advanced, targeted cyber attacks. This paper describes the design and implementation of the Trusted Dynamic Logical Heterogeneity System (TALENT), a framework for live-migrating critical infrastructure applications across heterogeneous platforms. TALENT permits...

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Information security for situational awareness in computer network defense

Published in:
Chapter Six, Situational Awareness in Computer Network Defense: Principles, Methods, and Applications, 2011, pp. 86-103.

Summary

Situational awareness - the perception of "what's going on" - is crucial in every field of human endeavor, especially so in the cyber world where most of the protections afforded by physical time and distance are taken away. Since ancient times, military science emphasized the importance of preserving your awareness of the battlefield and at the same time preventing your adversary from learning the true situation for as long as possible. Today cyber is officially recognized as a contested military domain like air, land, and sea. Therefore situational awareness in computer networks will be under attacks of military strength and will require military-grade protection. This chapter describes the emerging threats for computer SA, and the potential avenues of defense against them.
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Summary

Situational awareness - the perception of "what's going on" - is crucial in every field of human endeavor, especially so in the cyber world where most of the protections afforded by physical time and distance are taken away. Since ancient times, military science emphasized the importance of preserving your awareness...

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Design, implementation and evaluation of covert channel attacks

Published in:
2010 IEEE Int. Conf. on Technologies for Homeland Security, 8 November 2010, pp. 481-487.

Summary

Covert channel attacks pose a threat to the security of critical infrastructure and key resources (CIKR). To design defenses and countermeasures against this threat, we must understand all classes of covert channel attacks along with their properties. Network-based covert channels have been studied in great detail in previous work, although several other classes of covert channels (hardware based and operating system-based) are largely unexplored. One of our contributions is investigating these classes by designing, implementing, and experimentally evaluating several specific covert channel attacks. We implement and evaluate hardware-based and operating system-based attacks and show significant differences in their properties and mechanisms. We also present channel capacity differences among the various attacks, which span three orders of magnitude. Furthermore, we present the concept of hybrid covert channel attacks which use two or more communication categories to transport data. Hybrid covert channels can be qualitatively harder to detect and counter than traditional covert channels. Finally, we summarize the lessons learned through covert channel attack design and implementation, which have important implications for critical asset protection and risk analysis. The study also facilitates the development of countermeasures to protect CIKR systems against covert channel attacks.
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Summary

Covert channel attacks pose a threat to the security of critical infrastructure and key resources (CIKR). To design defenses and countermeasures against this threat, we must understand all classes of covert channel attacks along with their properties. Network-based covert channels have been studied in great detail in previous work, although...

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Secure channel establishment in disadvantaged networks: optimizing TLS using intercepting proxies

Published in:
MILCOM 2010, IEEE Military Communications Conference , 31 October-3 November 2010.

Summary

Transport Layer Security (TLS) is a secure communication protocol that is used in many secure electronic applications. In order to establish a TLS connection, a client and server engage in a handshake, which usually involves the transmission of digital certificates. In this paper we present a practical speedup of TLS handshakes over bandwidth-constrained, high-latency (i .e. disadvantaged) links by reducing the communication overhead associated with the transmission of digital certificates. This speedup is achieved by deploying two specialized TLS proxies across such links. Working in tandem, one proxy replaces certificate data in packets being sent across the disadvantaged link with a short reference, while the proxy on the other side of the link restores the certificate data in the packet. Local or remote caches supply the certificate data. Our solution preserves the end-to-end security of TLS and is designed to be transparent to third-party applications, and will thus facilitate rapid deployment by removing the need to modify existing installations of TLS clients and TLS servers. Testing shows that this technique can reduce the overall bandwidth used during a handshake by 50% in test emulation and by over 20% of TLS session volume in practice. In addition, it can reduce the time required to establish a secure channel by over 40% across Iridium, a widely used satellite link in practice.
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Summary

Transport Layer Security (TLS) is a secure communication protocol that is used in many secure electronic applications. In order to establish a TLS connection, a client and server engage in a handshake, which usually involves the transmission of digital certificates. In this paper we present a practical speedup of TLS...

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TALENT: dynamic platform heterogeneity for cyber survivability of mission critical applications

Published in:
Proc. Secure and Resilient Cyber Architecture Conf., SRCA, 29 October 2010.

Summary

Despite the significant amount of effort that often goes into securing mission critical systems, many remain vulnerable to advanced, targeted cyber attacks. In this work, we design and implement TALENT (Trusted dynAmic Logical hEterogeNeity sysTem), a framework to live-migrate mission critical applications across heterogeneous platforms. TALENT enables us to change the hardware and operating system on top of which a sensitive application is running, thus providing cyber survivability through platform diversity. Using containers (a.k.a. operating system-level virtualization) and a portable checkpoint compiler, TALENT creates a virtual execution environment and migrates a running application across different platforms while preserving the state of the application. The state, here, refers to the execution state of the process as well as its open files and sockets. TALENT is designed to support a general C application. By changing the platform on-the-fly, TALENT creates a moving target against cyber attacks and significantly raises the bar for a successful attack against a critical application. Our measurements show that a full migration can be completed in about one second.
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Summary

Despite the significant amount of effort that often goes into securing mission critical systems, many remain vulnerable to advanced, targeted cyber attacks. In this work, we design and implement TALENT (Trusted dynAmic Logical hEterogeNeity sysTem), a framework to live-migrate mission critical applications across heterogeneous platforms. TALENT enables us to change...

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GROK: a practical system for securing group communications

Published in:
NCA 2010, 9th IEEE Int. Symp. on Network Computing and Applications, 15 July 2010, pp. 100-107.

Summary

We have designed and implemented a general-purpose cryptographic building block, called GROK, for securing communication among groups of entities in networks composed of high-latency, low-bandwidth, intermittently connected links. During the process, we solved a number of non-trivial system problems. This paper describes these problems and our solutions, and motivates and justifies these solutions from three viewpoints: usability, efficiency, and security. The solutions described in this paper have been tempered by securing a widely-used group-oriented application, group text chat. We implemented a prototype extension to a popular text chat client called Pidgin and evaluated it in a real-world scenario. Based on our experiences, these solutions are useful to designers of group-oriented systems specifically, and secure systems in general.
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Summary

We have designed and implemented a general-purpose cryptographic building block, called GROK, for securing communication among groups of entities in networks composed of high-latency, low-bandwidth, intermittently connected links. During the process, we solved a number of non-trivial system problems. This paper describes these problems and our solutions, and motivates and...

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Data diodes in support of trustworthy cyber infrastructure

Published in:
6th Annual Cyber Security and Information Intelligence Research Workshop, Cyber Security and Information Intelligence Challenges and Strategies, CSIIRW10, 21 April 2010.

Summary

Interconnections between process control networks and enterprise networks has resulted in the proliferation of standard communication protocols in industrial control systems which exposes instrumentation, control systems, and the critical infrastructure components they operate to a variety of cyber attacks. Various standards and technologies have been proposed to protect industrial control systems against cyber attacks and to provide them with confidentiality, integrity, and availability. Among these technologies, data diodes provide protection of critical systems by the means of physically enforcing traffic direction on the network. In order to deploy data diodes effectively, it is imperative to understand the protection they provide, the protection they do not provide, their limitations, and their place in the larger security infrastructure. In this work, we briefly review the security challenges in an industrial control system, study data diodes, their functionalities and limitations, and propose a scheme for their effective deployment in trusted process control networks (TPCNs.)
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Summary

Interconnections between process control networks and enterprise networks has resulted in the proliferation of standard communication protocols in industrial control systems which exposes instrumentation, control systems, and the critical infrastructure components they operate to a variety of cyber attacks. Various standards and technologies have been proposed to protect industrial control...

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