Flavio Bergamaschi

Utility-based bandwidth adaptation in mission-oriented wireless sensor networks

This article develops a utility-based optimization framework for resource sharing by multiple competing missions in a mission-oriented wireless sensor network (WSN) environment. Prior work on network utility maximization (NUM) based optimization has focused on unicast flows with sender-based utilities in either wireline or wireless networks. In this work, we develop a generalized NUM model to consider three key new features observed in mission-centric WSN environments: i) the definition of the utility of an individual mission (receiver) as a joint function of data from multiple sensor sources; ii) the consumption of each senders (sensor) data by multiple missions; and iii) the multicast-tree-based dissemination of each sensors data flow, using link-layer broadcasts to exploit the “wireless broadcast advantage” in data forwarding. We show how a price-based, distributed protocol (WSN-NUM) can ensure optimal and proportionally fair rate allocation across multiple missions, without requiring any coordination among missions or sensors. We also discuss techniques to improve the speed of convergence of the protocol, which is essential in an environment as dynamic as the WSN. Further, we analyze the impact of various network and protocol parameters on the bandwidth utilization of the network, using a discrete-event simulation of a stationary wireless network. Finally, we corroborate our simulation-based performance results of the WSN-NUM protocol with an implementation of an 802.11b network.

ITA Sensor Fabric

The diverse sensor types and networking technologies commonly used in fielded sensro networks provide a unique set of challenges [1] in the areas of sensor identification, interoperability, and sensor data consumability. The ITA Senor Fabric is a middleware infrastructure - developed as part of the International Technology Alliance (ITA)[2] in Network and Information Science - that addresses these challenges by providing unified access to, and management of, sensor networks. The Fabric spans the network from command and control, through forward operating bases, and out to mobile forces and fielded sensors, maximizing the availability and utility of intelligence information to users.

ITA/CWP and ICB technology demonstrator: a practical integration of disparate ISR/ISTAR assets and technologies

This paper presents the results of a US-UK collaboration project sponsored by the Coalition Warfare Program (CWP) of the Office of the Secretary of Defense (OSD). The goal of this project was to integrate a single framework a set of sensor and policy tools and protocols to enable the rapid assembly and deployment of a disparate set of coalition assets combined into a sensor network with policy controlled sharing/dissemination of data and information. This project was based on two key technology components developed as part of the International Technology Alliance in Network and Information Science (ITA) - the Information Fabric and the Policy Management Toolkit, and technology components developed by the Institute for Collaborative Biotechnologies (ICB) - the Autonomous UAV Persistent Surveillance using Bio-Inspired Strategies.

Network Science collaborative experimentation methods and tools to accelerate network science innovation within the ITA and NS-CTA

Network Science research within the ITA and NS-CTA explores the challenges and emerging directions for networked armed forces. This paper presents the justification, methodology and supporting tools built by the alliance to promote deeper collaboration among its members in order to accelerate the pace of research and further connect basic research with Army relevance. Our approach leverages virtualization, dynamic network provisioning and high-fidelity network simulation techniques for modeling, reproducing and extending complex distributed multi-genre network experimentation with research capabilities that can be readily enlisted by the consortium researchers.

Service-oriented reasoning architecture for resource-task assignment in sensor networks

The net-centric ISR/ISTAR networks are expected to play a crucial role in the success of critical tasks such as base perimeter protection, border patrol and so on. To accomplish these tasks in an effective and expedient manner, it is important that these networks have the embedded capabilities to discover, delegate, and gather relevant information in a timely and robust manner. In this paper, we present a system architecture and an implementation that combines a service based reasoning mechanism with a sensor middleware infrastructure so that tasks can be executed efficiently and effectively. A knowledge base, utilising the Semantic Web technologies, provides the foundation for reasoning mechanism that assists users to discover, identify and allocate resources that are made available through the middleware, in order to satisfy the needs of tasks. Once resources are allocated to any given task, they can be accessed, controlled, shared, and their data feeds consumed through the Fabric middleware. We use the semantic descriptions from the knowledge base to annotate the resources (types, capabilities, etc.) in the sensor middleware so that they can be retrieved for reasoning during the discovery and identification phases. The reasoner is implemented as a HTTP web service, with the following characteristics: 1. Computational intensive operations are off-loaded to dedicated nodes, preserving the resources in the ISR/ISTAR networks. 2. HTTP services are accessible through a standard set of APIs irrespective of the reasoner technology used. 3. Support for seamless integration of different reasoners into the system.

Agile sensor tasking for CoIST using natural language knowledge representation and reasoning

We describe a system architecture aimed at supporting Intelligence, Surveillance, and Reconnaissance (ISR) activities in a Company Intelligence Support Team (CoIST) using natural language-based knowledge representation and reasoning, and semantic matching of mission tasks to ISR assets. We illustrate an application of the architecture using a High Value Target (HVT) surveillance scenario which demonstrates semi-automated matching and assignment of appropriate ISR assets based on information coming in from existing sensors and human patrols operating in an area of interest and encountering a potential HVT vehicle. We highlight a number of key components of the system but focus mainly on the human/machine conversational interaction involving soldiers on the field providing input in natural language via spoken voice to a mobile device, which is then processed to machine-processable Controlled Natural Language (CNL) and confirmed with the soldier. The system also supports CoIST analysts obtaining real-time situation awareness on the unfolding events through fused CNL information via tools available at the Command and Control (C2). The system demonstrates various modes of operation including: automatic task assignment following inference of new high-importance information, as well as semi-automatic processing, providing the CoIST analyst with situation awareness information relevant to the area of operation.

Characterization and definition of a software stack for a reference experimental framework

In 2006, the US Army Research Laboratory (ARL) and the UK Ministry of Defence (MoD) established a collab orative research alliance with academia and industry, named the International Technology Alliance in Network and Information Science (ITA) 1 to address fundamental issues concerning Network and Information Sciences. Research performed under the ITA was extended through a collaboration between ARL and IBM UK to char acterize and define a software stack and tooling that will become the reference framework for network science experimentation. A key element to the success and validation of ITA theoretical research is experimentation in a controlled environment that can, as best as possible, emulate the real world conditions and context. Ex perimental validation in a network emulation environment contributes to the validation of theoretical concepts and algorithms, the investigation of more complex scenarios that span multiple research areas, exposing gaps in the theory that may need special attention, identifying additional areas where the research might focus and develop, and reproducible experimentation, which enables and facilitates the comparison of results from multiple executions of the same experiment. To accomplish these experimentation goals, the framework needs to foster the collaboration across multiple disciplines and facilitate the sharing of existing and new assets in a common emulation environment. The framework also needs to be extensible for the integration of new features, emula tion models, monitoring, and integration with real, external assets that can be linked to any given experiment. This paper discusses the work resulting from the ARL/ IBM UK collaboration to build a framework to support experimentations and foster collaboration within and across different research groups.

Forecasting routes and self-adaptation in multi-hop wireless sensor networks

Sensor networks find application in many tactical ISR/ISTAR processes and applications. However, these processes and applications depend on reliable collection, distribution and delivery of information that, typically, travels over multiple interconnecting nodes to reach processing centres, and are susceptible to various disruptions such as the ones caused caused by message drops, packet loss and loss of connectivity due to high traffic volumes and noise on the wireless medium. In this paper, we investigate and present approaches to pro-actively adapt routing over such networks by forecasting potential faulty regions of the network based on previous trends and reorganising routing paths. We have prototyped this approach in the ITA Sensor Fabric, an evolving middleware infrastructure for sensor networks. We, further, provide some preliminary results based on simulations.

Model-driven SOA for sensor networks

Our previous work has explored the application of enterprise middleware techniques at the edge of the network to address the challenges of delivering complex sensor network solutions over heterogeneous communications infrastructures. In this paper, we develop this approach further into a practicable, semantically rich, model-based design and analysis approach that considers the sensor network and its contained services as a service-oriented architecture. The proposed model enables a systematic approach to service composition, analysis (using domain-specific techniques), and deployment. It also enables cross intelligence domain integration to simplify intelligence gathering, allowing users to express queries in structured natural language (Controlled English).

Computing on encrypted data and its applicability to a coalition operations environment

Coalition operations often invoke the sharing of information and IT infrastructure amongst partners. Whilst there may be a coalition ‘need to share’ data this is often tempered by a ‘need to know’ principle that often prevents valuable information from being exchanged, particularly with classified data. Ideally, coalition partners would wish to share data that can be used to compute specific results that are only relevant to a given operation, without revealing all of the shared information. In this paper we will present the concept of a secure coalition cloud architecture that is capable of storing encrypted data and of performing arbitrary computations on the encrypted data on behalf of users, without at any stage having to decrypt it. To do this we make use of a fully homomorphic encryption scheme using a novel approach for managing encryption and decryption keys in a public key infrastructure (PKI) setting.