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Although security is a crucial issue for information systems, traditionally, it is considered after the definition of the system. This approach often leads to problems, which most of the times translate into security vulnerabilities. From the viewpoint of the traditional security paradigm, it should be possible to eliminate such problems through better integration of security and software engineering. This paper firstly argues for the need to develop a methodology that considers security as an integral part of the whole system development process, and secondly it contributes to the current state of the art by proposing an approach that considers security concerns as an integral part of the entire system development process and by relating this approach with existing work. The different stages of the approach are described with the aid of a real-life case study; a health and social care information system.

Older people often have a complex mixture of health and social care needs and several different health and social care professionals are involved in their care. National policy in England is to promote the single assessment process (SAP), an integrated assessment of health and social care needs of older people. However, most of the current information systems do not adequately provide the functionality that is required by health and social care professionals. In this paper we discuss the suitability of agent technology, explaining why we selected it as offering the greatest potential for efficient and flexible information collection and sharing, and for supporting effective care planning. Also, we point out benefits derived from the use of agent technology in the development of health and social care systems, such as the minimization of health and social care professionals' workload. In addition, we describe how we have developed a model for an integrated information system, based on agent technology, for health and social care needs assessment of older people. Finally, we discuss issues, such as security and mobility, involved in the development of such a system, which will need to be designed and tested prior to its implementation in health and social care practice.

Health care information systems are becoming more and more computerized. A huge amount of health related information needs to be stored and analysed, and with the aid of computer systems this can be done faster and more efficiently. The Agent Oriented paradigm provides an alternative way of developing medical based systems. This article presents an initial exploration of the analysis and design of a multi-agent system to deliver the Single Assessment Process, an integrated health and social care information system for older people. The article concludes by making the following observations: Agent technology has the potential to support the development of medical and health and social care systems for older people. Nevertheless there are not many real-life agent based applications successfully applied in the health care sector. One of the main reasons is the limitation of the existing analysis and design methodologies. Thus, in order for the agent-technology to be widely accepted in the development of computer based medical information systems for older people (and in extent any medical system) it is necessary to develop a complete and mature analysis and design methodology to support the development of agent based medical systems.

The growing dependence of modern society on telecommunication and information networks and e‐type systems has become inevitable. However, those types of systems are vulnerable to malicious attacks. The speed and automation in network attack techniques continue to increase. An achievable automated attack or unauthorised access to a particular organization network could lead to devastating effects on its reputation and imminent loss of life. In this paper an innovative way is proposed to detect network attacks of a distributed nature such as denial of service (DoS) attacks. The proposed scheme is mainly based on neuro‐fuzzy intelligence in order to learn and determine the fuzzy parameter functions that represent network traffic behaviour. Neuro‐fuzzy agents combine the features of fuzzy logic and neural networks and they have been proposed to overcome the limitations of human expertise in defining fuzzy membership functions, especially for complex environments, such as information networks.

In today’s society, information and communications technology (ICT) is the force that drives prosperity and provides a higher standard of living. All other e‐services and infrastructures tend to play a major role in our daily life and global economy. The growing dependence on such systems, however, has increased their vulnerability to cyber attacks. Any failure to these systems typically would lead to a huge impact, not only on businesses, but also human life, that depends on such interconnected systems. The growing potential for telecommunications network infrastructures problems stems from their nature of openness. A successful attempt for a network attack to a particular organization’s network could have devastating effects on the security of the organisation. In this paper we propose an innovative way to counteract distributed protocols attacks such as distributed denial of service (DDoS) attacks using intelligent fuzzy agents.

A methodology called Parallel Communicating Sequential Code (PCSC) is currently being researched and developed for designing and coding parallel system software. To implement this methodology a parallel CASE tool is also being developed and refined hand-in-hand. The underlying philosophy behind the PCSC methodology is consistency between design, program code, configuration and documentation. Design is captured via pictures (diagrams) and annotations (text). The diagrams and text completely define a parallel design. They form an abstract language from which program code is to be derived automatically. Configuration refers to the specification of the software and hardware as well as mapping between them. Documentation involves generation of reports and documents on all aspects of the methodology. Automation (full or partial) is seen as the key player for ensuring consistency between the four main aspects of the methodology.

The use of two types of parallel computer hardware for increasing the efficiency of processing in chemical structure data bases is discussed. The distributed array processor can be used for the clustering of 2-D chemical structure data bases by using the Jarvis—Patrick clustering method and for the ranking of output in an experimental system for substructure searching in the 3-D macromolecules in the Protein Data Bank. The Inmos transputer can be used in the construction of PC-based systems for 2-D substructure searching and in the identification of the maximal substructures common to pairs of 3-D molecules.

A Mobile Ad hoc NETwork (MANET) is considered to be a self-organised network formed by wireless mobile nodes without any existing infrastructures. In the future, it is very likely every person and vehicle will have wireless communication capability in a city environment. The resulting information network can be viewed as a typical MANET with the characteristics of conventional ad hoc networks and Inter-Vehicle Communication (IVC) system with node heterogeneity. Due to various movement behaviors of mobile nodes, space constraints and obstacles effect, the MANET in the city environment can exhibit significantly different characteristic. This paper studies this particular MANET and the characteristics of the mobile nodes in the city environment, and discusses on the solutions for enhancing the routing performance. The city environment is constructed by a novel City-IVC Mobility model, and a typical IVC system, called the RoadLamp-aided IVC system is introduced and compared with the Bus-aided IVC system. The impact on the routing performance in both systems is extensively studied and compared by simulating the conventional protocol AODV

Simulation is the most important and widely used method in the research of Mobile Ad hoc NETworks (MANET). The topology of MANET and the mobility of mobile nodes are the key factors that have an impact on the performance of protocols. However, most of the existing works are based on random movement and the fact that the network topology is highly related to the environment of MANET is overlooked. In this paper, we propose a novel Environment-Aware Mobility (EAM) model which models a more realistic movement of mobile nodes. Environment objects such as Route and Hotspot are introduced to represent the environment components which are rendered by Scalable Vector Graphics (SVG). It is considered to be a complex model with a combination of existing conventional mobility models and network environments. This paper shows that various MANET environments can be modeled based on this work. A sample environment is also simulated and the results show that the intrinsic characteristics and properties of the environments have a significant influence on the performance of MANET protocols.

Self-organisation is one of the most important characteristics of mobile ad hot network (MANET). The performance of protocols proposed for the MANET is usually evaluated by performing extensive simulations. Research has shown that the simulation results are highly dependent on the movement behaviours (mobility models; of mobile nodes. However, most of the mobility models are random-based where some of the important factors related to the simulation environment are not taken into account. In this paper, two realistic mobility models we proposed route mobility model and hotspot mobility model which present the typical environments where road and attractive places exist, respectively. In these models the movements of mobile nodes are either restricted to the pre-defined route or influenced by the hotspot. The results show that the environment factors such as spatial constraints and speed limits may cause significant impact on the network performance.

Simulation is the most important and widely used method in the research of Mobile Ad hoc NETworks (MANET). The topology of MANET and the mobility of mobile nodes are the key factors that have impact on the performance of protocols. However, most of the existing works are based on random movement, and the fact that the network topology is highly related to the environment of MANET is overlooked. In this paper, we propose a novel Environment-Aware Mobility (EAM) model which models a more realistic movement of mobile nodes. Environment objects such as Route and Hotspot, etc are introduced to represent the environment components by Scalable Vector Graphics (SVG). This model is considered to be a complex model with a combination of existing conventional mobility models and network environments. The results show that the intrinsic characteristics and properties of the environments have a significant influence on the performance of MANET protocols.

Bluetooth is a typical short-range radio packet ad-hoc technique that is attractive in the rapid formation of a personal area network and inter-connection of different portable mobile devices. Compared with many high-speed wireless LAN techniques, Bluetooth provides a moderate link speed because each link is only allocated with 1 MHz bandwidth. In order to increase the link utilization, Bluetooth introduces the flexible usage of asymmetric link capacity allocation. It means different speeds are allowed in two directions of a link that flow from the master to the slave and from the slave to the master. Because of this, it is possible for Bluetooth to adaptively adjust the link capacity distribution to increase the link performance with lower latency. In this paper, we use the delay cost function to analyse the capacity assignment for a Bluetooth link. Although it only focuses in solving the capacity assignment of a single link, it is also applicable to large-size multi-link and multi-hop networks. It could be extended to generic data networks with asymmetric links.

This paper demonstrates how UML can be exploited and extended to model the deployment of a multiagent system at the agent level. This is accomplished by extending the formally-based UML 2.0 metamodel to support the semantics of agents, mobile agents and their supporting platforms. Additionally, the UML-based notation, used to model the deployment of a multiagent system, takes advantage of stereotypes to associate an agent-oriented semantics with the model elements used in the diagram. A primary objective of this paper is to demonstrate that the Agent UML (AUML) deployment diagram can be successfully applied to real-world applications. This AUML work is organized as an activity within the FIPA Modeling Technical Committee.

Unlike most wireless techniques, Bluetooth uses time division duplex (TDD) to arrange the transmission slots so that it can avoid the collisions. In a Bluetooth piconet, a master node coordinates up to seven active slave nodes, which implies up to fourteen different active virtual links. The schedulers of the devices, especially the one in the master node, are in charge of all the transmission disciplines. Therefore, the policy of the scheduler will affect the networks performance of the piconet, like delay and throughput. Currently the Bluetooth scheduler uses a round robin policy to distribute the slots for different links. An enhancement scheme is presented by introducing the predictive link capacity assignment plus the multi-slot framing. The advantages of the corresponding methods is discussed, which lead to a possible practical design of a new scheduler that exploits a better performance of a Bluetooth piconet.

Security plays an important role in the development of multiagent systems. However, a careful analysis of software development processes shows that the definition of security requirements is, usually, considered after the design of the system. This is, mainly, due to the fact that agent oriented software engineering methodologies have not integrated security concerns throughout their developing stages. The integration of security concerns during the whole range of the development stages could help towards the development of more secure multiagent systems. In this paper we introduce extensions to the Tropos methodology to enable it to model security concerns throughout the whole development process. A description of the new concepts is given along with an explanation of how these concepts are integrated to the current stages of Tropos. An example from the health care sector is used to illustrate the above.

Medium access control (MAC) is an intermediate layer to manage the policy of link transmissions so that nodes in the same network segment can send packets without constant interference from other nodes. It should give each node the opportunity to transmit packets successfully. Most existing wireless LAN techniques use contention-enable MACs, which are statistical multiplexing algorithms to control multiaccess. Compared to them, regular division-based MACs, such as time division multiplexing (TDM) or frequency division multiplexing (FDM), are seldom used in wireless LANs due to the inefficiency that is shown by the inflexible dynamic bandwidth allocation to nodes. Quality of service (QoS) takes into account this inflexibility in resource reservation in order to grant enough resource to services, even when they are idle. As a result, link connection-oriented networks with mesh topology are considered a good research topic. The corresponding simulation model is required where most current simulation tools do not provide one directly. We present a simple link connection-oriented network simulation design in C without using any existing simulation packages. It can help researchers to design the overall simulation in other related areas, and later it could be extended to a complete simulation tool.

Applications and services for mobile devices can benefit substantially from the use of automatic repeat request (ARQ) link layer protocols for wireless connections. However, a drawback comes with their use when transferring mixed traffic type, which is the introduction of excessive and highly jittered transmission delay, which negatively affect the performance of both real-time and TCP traffic. Here, we propose a selective ARQ protocol which is capable of switching between ARQ and non-ARQ modes based on two policies which we have defined. Our first policy is based on the assumption that for real-time traffic minimisation of delay is more important than reliable transmission. The second policy is an extension of the first and introduces a mechanism, which monitors the length of the buffer queue to decide whether or not packets should be sent with or without ARQ. Results obtained in this research show that real-time traffic can be sent with minimal delay jitter and within certain time boundaries, whilst TCP throughput can be increased significantly.

A self-healing network is a ‘dream’ for every network designer today. Abstractly it is a network that capable of maintaining the availability of network services. This would not be impossible to be turned into a reality if the networks are embedded with intelligence. By having the intelligent capability the network can be self- managed in response to events that taken place within the network itself through the learning mechanisms. This paper presents the User Manager Agent System (UMAS) learning performance in controlling a request for network application session. ANFIS of Matlab v5.3 has been used to simulate the learning process in which it bases on the training data of network state. The work also had revealed some weaknesses of ANFIS in processing a large volume of training data sets and substantial amount of time taken for processing.

An extendible CASE tools environment is currently being researched at the Department of Computer Science, University of Sheffield. This environment is designed primarily for developing parallel system software but is configurable for other applications. It requires an underlying generic data repository to represent information about the system under development in a consistent and complete form. The representation must be independent of the source, and intended use, of its data.

Research activities in the fine chemicals industry involve the generation and analysis of huge amounts of chemical and biological data, and this has led to the development of highly sophisticated, computer-based, chemical information systems to support the research [ 11. Most chemical databases contain two-dimensional structural data, i.e. planar chemical structure diagrams, but there is also increasing interest in the processing of three-dimensional structural data, e.g. from X-ray crystallography and molecular mechanics studies. In this paper, we summarize work in our laboratory over the last 3 years which seeks to determine the utility of parallel hardware for the efficient processing of the structural data that are contained in chemical information systems. Two of the very many different types of parallel computer [2] are discussed, these being the ICL Distributed Array Processor and the INMOS transputer.

It has been argued that security concerns should inform all the stages of the development process of an agent-based system. However, this is not the case since current agent-oriented methodologies do not, usually, consider security concepts within their modelling ontology. In this paper we present extensions to the Tropos ontology to enable it to model security.