G. Matich

Selex Galileo, Washington, Washington, D.C., United States

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Publications (11)3.66 Total impact

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    ABSTRACT: This paper presents a mechanism for inferring user behaviour from encrypted wireless network activity. Aside from being within range, this mechanism operates without any level of network access, and without the need to break any encryption. It demonstrates how an entirely passive, external observer can detect if and when a person is using Skype. It is further demonstrated that this detection ability remains even when Skype traffic is interleaved with confounding simultaneous traffic such as BitTorrent. The metrics utilised by the detection process are a consequence of efficient data transfer. It is reasonable to believe that similar methods would be effective on the majority of modern wireless communications, and not specific to the protocols underlying the demonstration. The approach shown challenges the assumption that secure cryptography means secure information and adaptations of the mechanism used may help guide the analysis of increasingly large volumes of encrypted data.
    Wireless Communications and Networking Conference (WCNC), 2013 IEEE; 01/2013
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    ABSTRACT: Distributed unattended ground sensor networks used in battlefield surveillance and monitoring missions, have proven to be valuable in providing a tactical information advantage required for command and control, intelligence, surveillance, and reconnaissance planning. Operational effectiveness for surveillance missions can be enhanced further through network centric capability, where distributed UGS networks have the ability to perform surveillance operations autonomously. NCC operation can be enhanced through UGSs having the ability to evaluate their awareness of the current joint surveillance environment, in order to provide the necessary adaptation to dynamic changes. NCC can also provide an advantage for UGS networks to self-manage their limited operational resources efficiently, according to mission objective priority. In this article, we present a crosslayer approach and highlight techniques that have potential to enable NCC operation within a mission-orientated UGS surveillance setting.
    IEEE Communications Magazine 11/2011; · 3.66 Impact Factor
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    ABSTRACT: A system termed VIGILANT+ is outlined, which utilises situation awareness for the purposes of enabling distributed, autonomic, sensor management, so that savings on consumption of network resources can be achieved. VIGILANT+ is a novel proposition allowing deployed, unattended, wireless sensor nodes to self-organise into dynamic groups and self-manage their transmissions efficiently, according to a current common mission objective. First, a distributed situation assessment system named PORTENT model detects and characterises potential situations occurring within an uncertain environment, using the metric, quality of surveillance information. Secondly, a Bayesian belief network is utilised to understand and analyse the significance associated with the potential situation, primarily to enable deployed sensors to self-organise and assign themselves to mission objectives autonomously. Thirdly, a system is introduced for distributed autonomic transmission control, which enables the efficient management of sensor network resource consumption. Simulations have been undertaken to verify the integrated VIGILANT+ concepts and to demonstrate the effectiveness of the proposed approach in improving network efficiency, without compromising the presentation of mission surveillance utility.
    Wireless Sensor Systems, IET. 01/2011; 1(4):229-240.
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    ABSTRACT: Distributed unattended ground sensor (UGS) networks are deployed to support surveillance capabilities, within a security-sensitive region. Distributed operation can be enhanced through situational awareness, which is a three level integrated approach, involving perception, comprehension and projection, concerning the monitored threat. In this paper, we present a temporal projection process concerning the monitored threat, in order to allow efficient consumption of network resources through autonomic transmission control. Temporal projection can be formalized by utilizing a Partially Observable Markov Decision Process (POMDP). The POMDP can be further enhanced to achieve savings in UGS network resource consumption, by managing when decision epochs concerning transmission selection and priority scheduling should be taken. Rather than to take these decision epochs on every threat observation, we propose it is more efficient to adapt decision epoch frequencies according to monitored threat characteristics. In addition to the POMDP we also present strategies for managing decision epoch frequencies for autonomic transmission control decision making, according to the characteristics of the monitored threat. Simulations have been conducted to verify the network resource savings that can be achieved, while evaluating the surveillance utility provided, concerning the monitored threat, through using our proposed decision epoch interval strategies.
    MILITARY COMMUNICATIONS CONFERENCE, 2011 - MILCOM 2011; 01/2011
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    ABSTRACT: In this paper, we propose a distributed predator aware situation assessment system (PORTENT) to model and detect potential events occurring within an uncertain environment. PORTENT draws inspiration from how the mammalian brain detects and makes rational decisions through assessing fragmented signals of threat, within uncertainty, at different speeds. PORTENT represents the faster system using standard signal detection theory and the slower more accurate system as the integration of sensory data over time, until a certain level of confidence is reached. We also consider strategies to how both these systems could be combined optimally, to enhance PORTENT situation assessment performance. Our experimental simulations to verify the PORTENT concept demonstrates the effectiveness of our approach.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
    04/2010;
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    ABSTRACT: In this paper, we propose a distributed predator aware situation assessment system (PORTENT) to model and detect potential events occurring within an uncertain environment. PORTENT draws inspiration from how the mammalian brain detects and makes rational decisions through assessing fragmented signals of threat, within uncertainty, at different speeds. PORTENT represents the faster system using standard signal detection theory and the slower more accurate system as the integration of sensory data over time, until a certain level of confidence is reached. We also consider strategies to how both these systems could be combined optimally, to enhance PORTENT situation assessment performance. Our experimental simulations to verify the PORTENT concept demonstrates the effectiveness of our approach.
    Proc SPIE 04/2010;
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    ABSTRACT: Effective situation awareness is a critical element for decision support in a wide range of military and para-military operational surveillance scenarios. Effective situation awareness in a surveillance scenario can greatly increase operational effectiveness, by improving the quality and timeliness of decisions. In this paper we outline a three level integrated design approach to promote situation awareness. Our approach allows deployed wireless sensor nodes to efficiently self-organise into dynamic clusters, based on a current common perceived threat situation (context). Firstly our distributed predator aware situation assessment system (PORTENT) models, detects and presents, in terms of quality of information (QoI), potential situations occurring within an uncertain environment. Secondly, we utilise a Bayesian belief network to understand the significance associated with the potential situation. Finally in order to obtain a better shared awareness we have developed a "context aware" service protocol that supports group formation and efficient management of sensor network assets. By combining this three level approach, we present our VIGILANT "situation aware" QoI interest group system. Extensive simulations have been undertaken to verify the VIGILANT concept, to demonstrate the effectiveness of our approach, in improving performance for network management efficiency, through utilisation of a shared "context" service provision time and QoI surveillance presentation.
    01/2010;
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    ABSTRACT: For wireless sensor networks (WSN) involved in geographical surveillance type applications, obtaining information from a specified region of interest is important. The information itself is dependent upon the application type specific sensors deployed within the network region. For the purpose of this study we propose a new routing protocol called swarm intelligent odour based routing (SWOB) that uses network topology and geographic location information to coordinate effectively the routing tasks for information agents to traverse the network to the region of interest. SWOB applies the principles provided by social insects in odour localization. Using this natural principle SWOB uses a virtual Gaussian odour plume technique to describe the odour dispersion effects found in nature, allowing information agents in a distributed manner to be guided towards the region of interest effectively. Simulation results show the proposed scheme does indeed provide advantages on improving on latency by 98% and energy consumption performance by 75% when compared with basic flooding.
    Military Communications Conference, 2009. MILCOM 2009. IEEE; 11/2009
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    ABSTRACT: Throughput and energy efficiency are two important parameters to evaluate the performance of a wireless sensor network (WSN). For WSNs involved in varying channel conditions packet transmission reliability can be affected. This results in increased number of retransmissions and therefore energy consumption, with low throughput. Making optimal choices for robust packet transmission in this scenario is vital. For the purpose of this study a fuzzy logic system (FLS) is used as the decision mechanism for hop node selection. Both signal to noise ratio (SNR) and outage probability (Pout) are chosen parameters for the FLS, to decide upon hop node selection for reliable packet forwarding. Simulation results show that the proposed FLS does indeed provide advantages in improving on transmission reliability and energy efficiency performance, when operating in varying channel conditions.
    Telecommunications, 2009. ICT '09. International Conference on; 06/2009
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    ABSTRACT: Sensor networks represent a powerful new data paradigm facilitating the development of new intelligent applications. In support of mission critical applications such as surveillance, sensors can be made to operate effectively in their deployed environments by adopting a "situation awareness" perspective. In this paper we present and adapt our VIGILANT "situation aware" system architecture to cater for mission orientation, in terms of the perceived surveillance threat and communication channel environment. By taking a joint context view, we envisage deployed sensors to self-organise efficiently into dynamic ad-hoc groups, based on a current threat "situation" with added tolerance to communication link disruption, thus maintaining mission objectives and quality of service reliability.
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    D S Ghataoura, Y Yang, G Matich
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    ABSTRACT: Sensor networks represent a powerful new data paradigm facilitating the development of new intelligent applications. A sensor networks utility can be measured by the quality of information (QoI) that it provides for these applications. This paper focuses on the concept of QoI and a technique enabling efficient delivery of information to other parts of the sensor network, to facilitate decision making.