Mobile Systems Development - A literature review <s> PERSPECTIVES <s> It is expected that in the near future, tens of millions of users will have access to distributed information systems through wireless connections. The technical characteristics of the wireless medium and the resulting mobility of both data resources and data consumers raise new challenging questions regarding the development of information systems appropriate for mobile environments. In this paper, we report on the development of such a system. First, we describe the general architecture of the information system and the main considerations of our design. Then, based on these considerations, we present our system support for maintaining the consistency of replicated data and for providing transaction schemas that account for the frequent but predictable disconnections, the mobility, and the vulnerability of the wireless environment. <s> BIB001 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Two state-of-the-art design methodologies for embedded applications allowing rapid system prototyping are presented in this paper. These methodologies are currently under evaluation, for the development of a Mobile Communications Processor capable to undertake the execution of all the baseband processing of a Multi-mode Terminal supporting DECT and GSM/DCS protocols. <s> BIB002 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> In this paper, we investigate the issue of error control in wireless communication networks. We review the alternative error control schemes available for providing reliable end-to-end communication in wireless environments. Through case studies, the performance and tradeoffs of these schemes are shown. Based on the application environments and QoS requirements, the design issues of error control are discussed to achieve the best solution. <s> BIB003 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Extension of multimedia services and applications offered by ATM networks to wireless and mobile users has captured a lot of recent research attention. Research prototyping of wireless ATM networks is currently underway at many leading research and academic institutions. Various architectures have been proposed depending on the intended application domain. Successful implementation of wireless connectivity to ATM services is significantly dependent on the medium access control (MAC) protocol, which has to provide support for multimedia traffic and for quality-of-service (QoS) guarantees. The objective of this paper is to investigate the comparative performance of a set of access protocols, proposed earlier in the literature, with more realistic source traffic models. Data traffic is modeled with self-similar (fractal) behavior. Voice traffic is modeled by a slow speech activity detector (SAD). Video traffic is modeled as a H.261 video teleconference, where the number of ATM cells per video frame is described by a gamma distribution and a first-order discrete autoregressive process model. A comparison of the protocols based on simulation data is presented. The goal of the paper is to identify appropriate techniques for effectively and efficiently supporting multimedia traffic and QoS. Simulation results show that boundaries between different types of services are necessary for multimedia traffic. Reservation for certain traffic type especially video can significantly improve its quality. Reducing the number of collisions is an important issue for wireless networks since contentions lead not only to potentially high delay but also result in high power consumption. <s> BIB004 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> The IETF Mobile IP protocol is a significant step towards enabling nomadic Internet users. It allows a mobile node to maintain and use the same IP address even as it changes its point of attachment to the Internet. Mobility implies higher security risks than static operation. Portable devices may be stolen or their traffic may, at times, pass through links with questionable security characteristics. Most commercial organizations use some combination of source-filtering routers, sophisticated firewalls, and private address spaces to protect their network from unauthorized users. The basic Mobile IP protocol fails in the presence of these mechanisms even for authorized users. This paper describes enhancements that enable Mobile IP operation in such environments, i.e., they allow a mobile user, out on a public portion of the Internet, to maintain a secure virtual presence within his firewall-protected office network. This constitutes what we call a Mobile Virtual Private Network (MVPN). <s> BIB005 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> As Wireless Local Area Networks (WLANs) are rapidly deployed to expand the field of wireless products, the provision of authentication and privacy of the information transfer will be mandatory. These functions need to take into account the inherent limitations of the WLAN medium such as limited bandwidth, noisy wireless channel and limited computational power. Moreover, some of the IEEE 802.11 WLAN characteristics such as the use of a point coordinator and the polling based Point Coordination Function (PCF) have also to be considered in this design. In this paper, we introduce a security protocol for the IEEE 802.11 PCF that provides privacy and authentication, and is designed to reduce security overheads while taking into account the WLAN characteristics. We prove this protocol using the original and modified BAN logic. <s> BIB006 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Recent advances in wireless data networking and portable information appliances have engendered a new paradigm of computing, called mobile computing , in which users carrying portable devices have access to data and information services regardless of their physical location or movement behavior. In the meantime, research addressing information access in mobile environments has proliferated. In this survey, we provide a concrete framework and categorization of the various ways of supporting mobile client-server computing for information access. We examine characteristics of mobility that distinguish mobile client-server computing from its traditional counterpart. We provide a comprehensive analysis of new paradigms and enabler concepts for mobile client-server computing, including mobile-aware adaptation, extended client-server model, and mobile data access. A comparative and detailed review of major research prototypes for mobile information access is also presented. <s> BIB007 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> This paper introduces a 3-level multiagent architecture for QoS control in WATM. The ultimate aim of the proposed architecture is to provide a self-regulating network congestion control management by means of global network state awareness and agent interactions. The agents dynamically manage the buffer space at the level of a switch and interact to reduce the cell loss ratio while guaranteeing a bounded transit delay. We particularly address video transmission over UBR services using a per-VP queuing approach and an adaptive cell discarding congestion control scheme. Furthermore, a dynamic reconfiguration of the agents is performed during handoffs in order to continue meeting user end-to-end QoS requirements. The handoff delay absorption is also addressed. <s> BIB008 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Application-driven, technology-intensive research is critically needed to meet the challenges of globalization, interactivity, high productivity, and rapid adaptation faced by business organizations. Information systems researchers are uniquely positioned to conduct such research, combining computer science, mathematical modeling, systems thinking, management science, cognitive science, and knowledge of organizations and their functions. We present an agenda for addressing these challenges as they affect organizations in heterogeneous and distributed environments. We focus on three major capabilities enabled by such environments: Mobile Computing, Intelligent Agents, and Net-Centric Computing. We identify and define important unresolved problems in each of these areas and propose research strategies to address them. <s> BIB009 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Outlines an ongoing research project on training, education and sharing of experiences among mobile people, also referred to as nomads. The importance for professionals to continuously learn is widely recognized. Organizations in the new economy are dependent on organizational knowledge and competence. Mobile workers need alternative educational and knowledge development opportunities that are not restrained by time and space. The goal is providing competence development for nomads using 3rd generation cellular networks-3G, which combines high-speed mobile access with Internet Protocol (IP) based services. This allows mobile high quality multimedia. We present a preliminary study of the competence development situation of nomads. We outline two use cases of possible competence development activities suited for the mobile worker and the 3G platform. <s> BIB010 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> In this paper, we propose an approach to support QoS for multimedia applications in ad hoc wireless network. An ad hoc network is a collection of mobile stations forming a temporary network without the aid of any centralized coordinator and is different from cellular networks which require fixed base stations interconnected by a wired backbone. It is useful for some special situations, such as battlefield communications and disaster recovery. The approach we provide uses CSMA/CA medium access protocol and additional reservation and control mechanisms to guarantee quality of service in ad hoc network system. The reason we choose CSMA protocol instead of other MAC protocols is that it is used in most of currently wireless LAN productions. Via QoS routing information and reservation scheme, network resources are dynamically allocated to individual multimedia application connections. <s> BIB011 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Focuses on two emerging technologies for constructing a mobile ad-hoc wireless local area network (WLAN): IEEE 802.11 and Bluetooth. The IEEE 802.11 standard is a good platform to implement a single-hop ad-hoc network because of its extreme simplicity. Furthermore, multi-hop networks covering areas of several square kilometers could be built by exploiting the IEEE 802.11 technology. On smaller scales, technologies like Bluetooth can be exploited (perhaps in combination with the 802.11-type technology) to build ad-hoc wireless personal area networks (PANs), i.e. networks that connect devices placed inside a circle with radius of 10 meters. This paper presents, in a tutorial style, the architectures and protocols of IEEE 802.11 and Bluetooth. In addition, a discussion on the performance of these two technologies is presented. Specifically, we focus on the medium access control (MAC) protocol adopted by the two technologies and we analyze both the protocol efficiency (channel utilization) and the response time. <s> BIB012 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> The Wireless Application Protocol (WAP) is an open, global specification that empowers mobile users with wireless devices (such as mobile phones) to easily access and interact with information and services on the Internet. Although some components of the WAP suite have been developed, it lacks a complete general architecture integrating software components of both the Internet and wireless contexts in a transparent way. This paper presents a general architectural framework to develop and deploy portable applications and services accessible by WAP-compliant mobile terminals, extending end-to-end services between terminal and business applications. Different implementation strategies for the application logic are presented, allowing either fast prototyping or the realisation of robust, portable, complex applications and transactional services. Moreover, a technique to handle terminal disconnection is presented. <s> BIB013 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Abstract With the rapidly increasing penetration of laptop computers, which are primarily used by mobile users to access Internet services, support of Internet services in a mobile environment become an increasing need. The opportunities emerging from these technologies give rise to new paradigms such as mobile computing and ubiquitous networking . However, there are numerous challenges such as reliability and quality of service, infrastructure costs, energy efficiency of mobile devices, among others. This paper analyzes concepts, technologies and challenges related to these paradigms. The major challenges include mobility, disconnection and scale, new information medium and new resource limitations. As a fundamental characteristics of mobile environments, the user can see the same computing environment regardless of his or her current location. The most exciting promises of mobile computing and ubiquitous networking stay an entire new class of applications and potential new massive markets combining personal computing and consumer electronics. <s> BIB014 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> This paper tries to serve as an introductory reading to privacy issues in the field of ubiquitous computing. It develops six principles for guiding system design, based on a set of fair information practices common in most privacy legislation in use today: notice, choice and consent, proximity and locality, anonymity and pseudonymity, security, and access and recourse. A brief look at the history of privacy protection, its legal status, and its expected utility is provided as a background. <s> BIB015 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> The main driving force for the rapid acceptance rate of small sized mobile devices to do e-commerce is its increased convenience and efficiency in performing simple transactions compared with the stationary machines. Two of the weaknesses of this type of e-commerce are: (1) due to its small size, a mobile device can easily get lost and get stolen; (2) and it is neither very convenient nor cheap for a mobile user to perform transactions that require more than just a few messages, scanning of catalogues, or negotiations. Personal identification numbers (PIN) are currently used both for protection of the devices and for authentication of the user to solve (1). Sophisticated thefts might still uncover the PIN inside the mobile devices. (2) has not deserved much attention by the research community so far. We propose to use agent technology to cope with both problems. The related protocols are presented and the improvements on the security over the existing schemes are studied. <s> BIB016 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> This paper reports on the results of a Wireless Application Protocol (WAP) usability study, which consists of a survey, an evaluation of two UK WAP portals and an experiment that was carried out between November 2001 and February 2002. A number of usability issues, which prevented the users from completing basic and common tasks, were identified. For instance, 70 per cent of the users were not successful in searching for a textbook on the Amazon.co.uk WAP site. Additionally, even experienced users were not immune to these problems. The general conclusion of the study is that WAP usability remains poor. We argue that this could have a negative effect on the future of WAP and m‐commerce. Finally, we propose a set of ten principles, which are based on the findings of this study, and we believe will aid towards the development of more usable WAP and m‐commerce services. <s> BIB017 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Future wireless networks will offer near-ubiquitous high-bandwidth communications to mobile users. In addition, the accurate position of users will be known, either through network services or via additional sensing devices such as GPS. These characteristics of future mobile environments will enable the development of location-aware and, more generally, context-sensitive applications. In an attempt to explore the system, application, and user issues associated with the development and deployment of such applications, we began to develop the Lancaster GUIDE system in early 1997, finishing the first phase of the project in 1999. In its entirety, GUIDE comprises a citywide wireless network based on 802.11, a context-sensitive tour guide application with, crucially, significant content, and a set of supporting distributed systems services. Uniquely in the field, GUIDE has been evaluated using members of the general public, and we have gained significant experience in the design of usable context-sensitive applications. We focus on the applications and supporting infrastructure that will form part of GUIDE II, the successor to the GUIDE system. These developments are designed to expand GUIDE outside the tour guide domain, and to provide applications and services for residents of the city of Lancaster, offering a vision of the future mobile environments that will emerge once ubiquitous high-bandwidth coverage is available in most cities. <s> BIB018 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> The dawning of the 21st century has seen unprecedented growth in the number of wireless users, applications, and network access technologies. This trend is enabling the vision of pervasive ubiquitous computing where users have network access anytime, anywhere, and applications are location-sensitive and context-aware. To realize this vision, we need to extend network connectivity beyond private networks, such as corporate and university networks, into public spaces like airports, malls, hotels, parks, arenas, and so on - those places where individuals spend a considerable amount of their time outside private networks. In this article we argue that wireless LAN technologies are the ideal mechanism for extending network connectivity to these public places, and enabling location and context-aware applications in them. However, implementing and deploying public area wireless networks (PAWNs) present a number of practical challenges, including network security, privacy, authentication, mobility management, and provisioning of key services. We discuss these challenges as a general problem for PAWNs, and then describe a PAWN we have designed, implemented, and deployed called CHOICE that addresses them. We describe the architecture and components of CHOICE, the service models it supports, and the location services and context-aware applications we have implemented and deployed in it. <s> BIB019 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Full-scale adoption of mobile agent technology in untrustworthy network environments, such as the Internet, has been delayed by several security complexities [Montanari, 2001]. Presently, there is a large array of security issues and sub-issues within mobile agent computing that makes it tough to distinguish between different types of problems, and therefore also interfere with the definition of suitable solutions. Literature addressing the full range of problems is limited and mostly discusses single security threats or subsets of security problems and their possible solutions. The purpose of this paper is to analyse the different security threats that can possibly be imposed on agents by malicious hosts, and then provide a classification of these threats before we describe the current solution approaches that are implemented to address the identified problems. By providing such a classification we were able to identify specific gaps in current research efforts, and enable researchers to systematically focus their attention on different classes of solutions to remedy these threats. <s> BIB020 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> In this article we address delivering highly personalized context sensitive (i.e., time and location dependent) information to mobile clients. We believe providing highly personalized information to mobile clients from a variety of resources like e-mail servers, Web servers, and content providers will be an important service. Mobile network operators can play a major role in delivering this information to users by being strategically positioned between customers and content/service providers. Currently, many mobile network operators (MNO) and software companies are offering some personalized services. However the level of personalization is limited to choosing from available content links, icons and services. We believe that the mobile clients will benefit from a much higher level of personalization where it is possible to express complex queries involving a variety of data resources. For such a system to gain acceptance by the users, the process of defining personalized information (that is, user profiles) must be very easy for the user. The most important objective of such systems should be to provide scalability, that is, acceptable performance when the number of users increases dramatically. The article also elaborates on the nature of location dependent services. <s> BIB021 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Today, information sharing is critical to almost every institution. There is no more critical need for information sharing than during an international crisis, when international coalitions dynamically form. In the event of a crisis, whether it is humanitarian relief, natural disaster, combat operations, or terrorist incidents, international coalitions have an immediate need for information. These coalitions are formed with international cooperation, where each participating country offers whatever resources it can muster to support the given crisis. These situations can occur suddenly, simultaneously, and without warning. Often times, participants are coalition partners in one crisis and adversaries in another, raising difficult security issues with respect to information sharing. Our specific interest is in the Dynamic Coalition Problem (DCP), with an emphasis on the information sharing and security risks when coalitions are formed in response to a crisis. This paper defines the DCP and explores its intricate, challenging, and complex information and resource sharing, and security issues, utilizing real-world situations, which are drawn from a military domain. <s> BIB022 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> M-commerce, or mobile commerce, is a major application domain for mobile devices, enabling users to perform commercial transactions wherever they go. However, these applications require a high level of security. In this paper, the special characteristics of m-commerce are identified and some important security issues considered. <s> BIB023 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> This paper examines and reviews research methods applied within the field of mobile human-computer interaction. The purpose is to provide a snapshot of current practice for studying mobile HCI to identify shortcomings in the way research is conducted and to propose opportunities for future approaches. 102 publications on mobile human-computer interaction research were categorized in a matrix relating their research methods and purpose. The matrix revealed a number of significant trends with a clear bias towards building systems and evaluating them only in laboratory settings, if at all. Also, gaps in the distribution of research approaches and purposes were identified; action research, case studies, field studies and basic research being applied very infrequently. Consequently, we argue that the bias towards building systems and a lack of research for understanding design and use limits the development of cumulative knowledge on mobile human computer interaction. This in turn inhibits future development of the research field as a whole. <s> BIB024 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> In overlaying an existing cdma2000 network with a UMTS network, service transparency and number portability are important requirements for end users and hence the network operator. To support both requirements, one could introduce a protocol conversion node between the two networks; however, such a solution does not fully meet the requirements due to inherent technical constraints imposed by the differing standards. This article describes a network architecture based on the dual stack concept that satisfies the service transparency and number portability requirements across UMTS and cdma2000 networks, and also defines the functionality of the network nodes and the call processing procedures. <s> BIB025 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> A mobile ad hoc network (MANET) consists of mobile nodes communicating over wireless channels. Routing in MANETs is very challenging due to the random mobility of nodes and unreliability of wireless channels. Therefore most of the existing routing algorithms make only the best effort to find routes for communication but do not provide any performance guarantee. Because of the widespread use of MANETs in real-time applications, it becomes pertinent to provide deterministic network behavior. Quality of Service (QoS) aims to shape the network behavior and provide performance guarantees. In this work, a novel heuristic called Advanced-Optimised Link State Routing (A-OLSR) protocol is designed to provide QoS. It functions by enhancing the connectivity of nodes and establishing more stable routes as compared to standard best-effort Optimised Link State Routing (OLSR) protocol. The simulation results show that A-OLSR provides lower delay, reduces energy consumption and achieves higher throughput without introducing any additional routing overhead as compared to the standard OLSR and it's variants-A$$'$$?-OLSR and A$$''$$??-OLSR. The results also show that A-OLSR provides scalability since it's performance remains consistent with the increasing size of network. <s> BIB026 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> The ability to provide seamless and adaptive quality of service (QoS) in a heterogeneous environment is the key to the success of the next generation wireless communication systems. There has been a considerable amount of QoS research going on recently but the main portion still occurred in the context of individual architecture components and much less progress has been made in addressing the issue of an overall QoS architecture for the mobile Internet. In this article the state-of-the-art QoS techniques and standardization activities are summarized. Important challenges in building a ubiquitous QoS framework over the heterogeneous environment are examined in detail. Then a three-plane QoS framework based on QoS signaling architecture and policy framework is proposed to provide seamless support for future applications. <s> BIB027 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Mobile Ad-hoc Networks (MANET) is an emerging area of research. Most current work is centered on routing issues. This paper discusses the issues associated with data communication with MANET database systems. While data push and data pull methods have been previously addressed in mobile networks, the proposed methods do not handle the unique requirements associated with MANET. Unlike traditional mobile networks, all nodes within the MANET are mobile and battery powered. Existing wireless algorithms and protocols are insufficient primarily because they do not consider the mobility and power requirements of both clients and servers. This paper will present some of the critical tasks facing this research. <s> BIB028 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> The main driving force for the rapid acceptance rate of small sized mobile devices is the capability to perform e-commerce transactions at any time and at any place, especially while on the move. There are, however, also weaknesses of this type of e-commerce, often called mobile e-commerce, or m-commerce. Due to their small size and easy portability mobile devices can easily be lost or stolen. Whereas the economic values and privacy threats protected with Personal Identification Numbers (PIN) are not particularly high for normal voice-enabled mobile phones, this is not true any more when phones have developed to Personal Trusted Devices (PTDs). Still, PINs are used also in this new context for authorization and identification purposes. PINs are currently used both for protection of the devices and for authentication, as well as authorization of the users. It is commonly recognized that not many techniques of storing the PINs into the memory of the device or on the SIM card are safe. Even less sophisticated thieves might uncover the PIN inside the stolen mobile devices and for sophisticated thieves uncovering the PIN stored "safely" might be possible. In this paper we propose a new scheme to cope with the problem of uncovering the PIN that reduces the risks of m-commerce. The basic idea is that instead of storing the entire PIN digits (or some hash value) in the mobile device, we store part of the PIN in a remote machine in the network. The PIN verification then involves both the mobile device and the remote machine, which must verify their respective parts of the PIN. Also, the improvements of the security over the existing schemes are shown using a probabilistic model. In the best case, where the probability of discovering the PIN irrespective of the storage scheme is negligible in relation to directly uncovering it, the increase in security is over 1000%. <s> BIB029 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> In this paper we revisit the concept of mandatory access control and investigate its potential with personal digital assistants (PDA). Only if applications are clearly separated and Trojans cannot leak personal information can these PDAs become personal trusted devices. Limited processing power and memory can be overcome by using Web services instead of full-fledged applications - a trend also in non-mobile computing. Web services, however, introduce additional security risks, some of them specific for mobile users. We propose an identification scheme that can be effectively used to protect privacy and show how this system builds upon a light-weight version of mandatory access control. <s> BIB030 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> We present Road Rager, a prototype built in order to explore our hypothesis that proximity and a possibility to identify other players during temporary encounters could spur social interaction and enhance a mobile gaming experience. In this case, it is a multiplayer game designed to enable passengers in different cars to play against each other during a meeting in traffic. Using such meetings as resource opens new interesting possibilities for novel and engaging mobile experiences. In this paper we present the game concept, the implementation and the possibilities to interact - designed to successfully benefit from the dynamic and vivid mobile context created during a traffic encounter. We also present a technical test and some initial user feedback on the gaming experience. <s> BIB031 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Evaluating the usability of mobile systems raises new concerns and questions, challenging methods for both lab and field evaluations. A recent literature study showed that most mobile HCI research projects apply lab-based evaluations. Nevertheless, several researchers argue in favour of field evaluations as mobile systems are highly context-dependent. However, field-based usability studies are difficult to conduct, time consuming and the added value is unknown. Contributing to this discussion, this paper compares the results produced by a laboratory- and a field-based evaluation of the same context-aware mobile system on their ability to identify usability problems. Six test subjects used the mobile system in a laboratory while another six used the system in the field. The results show that the added value of conducting usability evaluations in the field is very little and that recreating central aspects of the use context in a laboratory setting enables the identification of the same usability problem list. <s> BIB032 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Location-based services (LBS), enabled by advances in mobile and positioning technologies, have afforded users with a pervasive flexibility to be uniquely addressable and to access network and services on-the-move. However, because LBS could also associate the lifestyle habits, behaviors, and movements with a consumer’s personal identity, privacy concerns are particularly salient for LBS. Drawing on psychological control and privacy literature, we designed an experiment study to test the basic proposition that the assurance of consumers’ perceived control over their personal information has a considerable influence on alleviating their privacy concerns. Three different mechanisms of assurance of control—technology, industry self-regulation, and legislation—were manipulated in the experiment, and their effects on consumers’ privacy concerns were examined. The results indicated that the technological assurance mechanism (i.e., mobile device in this study) played the most important role in assuring consumers’ perceived control over personal information. The marriage of the privacy and psychological control literature streams provides a rich understanding of consumers’ privacy reaction to LBS usage and, therefore, benefits the privacy and human-computer interaction (HCI) research in the Information Systems discipline. <s> BIB033 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> We study multi-access control in opportunistic communication systems, and propose two new schemes to address channel asymmetry and throughput-guaranteed admission control, respectively. We first devise a relay-aided opportunistic scheduling (RAOS) scheme, in which a user can choose to communicate with the base station either directly or using multiple hops (relay transmissions). We develop relay/direct link construction algorithms using either a channel-capacity-based criterion or a throughput-based criterion, and devise opportunistic scheduling schemes accordingly. Our results show that in the presence of channel asymmetry across users, the RAOS scheme performs significantly better than Qualcomm's HDR scheme. Next, we propose a traffic-aided smooth admission control (SAC) scheme that aims to guarantee throughput provisioning. Simply put, in the SAC scheme, the admission decision is "spread" over a trial period, by increasing gradually the amount of the time resource allocated to incoming users. Specifically, using the modified weighted proportional fair (WPF) scheduling, we devise a QoS driven weight adaptation algorithm, and the weights assigned to new users are increased in a guarded manner. Then an admission decision is made based on the measured throughput within a time-out window. A key feature is that we exploit explicitly the traffic information and throughput requirements in devising the back-off time. Our results show that the proposed SAC scheme works well in opportunistic communication systems. <s> BIB034 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> In the third-generation (and beyond) wireless communication systems, there will be a mixture of different traffic classes, each having its own transmission rate characteristics and quality-of-service (QoS) requirements. In this paper, a QoS-oriented medium access control (MAC) protocol with fair packet loss sharing (FPLS) scheduling is proposed for wireless code-division multiple access (CDMA) communications. The QoS parameters under consideration are the transmission bit error rate (BER), packet loss, and delay requirements. The MAC protocol exploits both time-division and code-division statistical multiplexing. The BER requirements are guaranteed by properly arranging simultaneous packet transmissions and controlling there transmit power levels, whereas the packet loss and delay requirements are guaranteed by proper packet scheduling. The basic idea of FPLS is to schedule the transmission of multimedia packets in such a way that all the users have a fair share of packet loss according to their QoS requirements, which maximizes the number of the served users under the QoS constraints. Simulation results demonstrate effectiveness of the FPLS scheduler, in comparison with other previously proposed scheduling algorithms. <s> BIB035 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> In this paper we propose a new software architecture for mobile agent toolkits. Agent toolkits mainly consist of a software system that forms an agency, which is responsible to host mobile and stationary software agents. In contrast to most architectures developed so far, which already define a large set of high-level services for agent migration and communication, we propose to employ a kernel-based approach. The kernel only provides fundamental concepts and functions and abstracts from any of these high-level services. We propose a new model for agencies and present our Tracy mobile agent toolkit acting as a reference implementation of our new model. <s> BIB036 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Next generation mobile devices will allow users to share and pass information within anonymous groups of people in an ad hoc manner. This will smooth the path for many kinds of new mobile commerce applications. In this paper we present a mobile commerce application that is part of the iClouds research project. It allows the dissemination of digital advertisements among interested mobile users. To create an incentive, an anonymous bonus point system rewards users who help to carry an advertisement from a merchant to a customer. This work includes a formal description of our bonus point model, a thorough discussion of the security goals, their realization and some first results about crypto-operation runtime behavior on a state-of-the-art PDA. <s> BIB037 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> This paper reports a new novel low-cost, wireless communication network system, called the "Electronic Shepherd" (ES). The system is innovative in the way that it supports flock behavior, meaning that a flock leader monitors the state of the other elements in the flock using low-cost radio communication equipment. The paper addresses both details of the terminal devices and communication protocols, as well as testing of the system in a real environment. The ES system was originally made to address special needs for sheep and reindeer farmers who were seeking a system to keep track of their animals during the grazing season. The system, including GPS receivers, UHF radio communication transceivers and GPRS modems, contributes a new approach for low-cost networking and service implementation, not only for the purpose of animal tracking, but also for other applications where objects are to be monitored at a low cost. <s> BIB038 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Rapid advances in wireless networking technologies have enabled mobile devices to be connected anywhere and anytime. While roaming, applications on these devices dynamically discover hosts and services with whom interactions can be started. However, the fear of exposure to risky transactions with potentially unknown entities may seriously hinder collaboration. To minimise this risk, an engineering approach to the development of trust-based collaborations is necessary. This paper introduces hTrust, a human trust management model and framework that facilitates the construction of trust-aware mobile systems and applications. In particular, hTrust supports: reasoning about trust (trust formation), dissemination of trust information in the network (trust dissemination), and derivation of new trust relationships from previously formed ones (trust evolution). The framework views each mobile host as a self-contained unit, carrying along a portfolio of credentials that are used to prove its trustworthiness to other hosts in an ad-hoc mobile environment. Customising functions are defined to capture the natural disposition to trust of the user of the device inside our trust management framework. <s> BIB039 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Many modern electronic systems---including personal computers, PDAs, cell phones, network routers, smart cards, and networked sensors to name a few---need to access, store, manipulate, or communicate sensitive information, making security a serious concern in their design. Embedded systems, which account for a wide range of products from the electronics, semiconductor, telecommunications, and networking industries, face some of the most demanding security concerns---on the one hand, they are often highly resource constrained, while on the other hand, they frequently need to operate in physically insecure environments.Security has been the subject of intensive research in the context of general-purpose computing and communications systems. However, security is often misconstrued by embedded system designers as the addition of features, such as specific cryptographic algorithms and security protocols, to the system. In reality, it is a new dimension that designers should consider throughout the design process, along with other metrics such as cost, performance, and power.The challenges unique to embedded systems require new approaches to security covering all aspects of embedded system design from architecture to implementation. Security processing, which refers to the computations that must be performed in a system for the purpose of security, can easily overwhelm the computational capabilities of processors in both low- and high-end embedded systems. This challenge, which we refer to as the "security processing gap," is compounded by increases in the amounts of data manipulated and the data rates that need to be achieved. Equally daunting is the "battery gap" in battery-powered embedded systems, which is caused by the disparity between rapidly increasing energy requirements for secure operation and slow improvements in battery technology. The final challenge is the "assurance gap," which relates to the gap between functional security measures (e.g., security services, protocols, and their constituent cryptographic algorithms) and actual secure implementations. This paper provides an introduction to the challenges involved in secure embedded system design, discusses recent advances in addressing them, and identifies opportunities for future research. <s> BIB040 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Security has become a primary concern in order to provide protected communication between mobile nodes in a hostile environment. Unlike the wireline networks, the unique characteristics of mobile ad hoc networks pose a number of nontrivial challenges to security design, such as open peer-to-peer network architecture, shared wireless medium, stringent resource constraints, and highly dynamic network topology. These challenges clearly make a case for building multifence security solutions that achieve both broad protection and desirable network performance. In this article we focus on the fundamental security problem of protecting the multihop network connectivity between mobile nodes in a MANET. We identify the security issues related to this problem, discuss the challenges to security design, and review the state-of-the-art security proposals that protect the MANET link- and network-layer operations of delivering packets over the multihop wireless channel. The complete security solution should span both layers, and encompass all three security components of prevention, detection, and reaction. <s> BIB041 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Using Data-Dependent (DD) Permutations (DDP) as main cryptographic primitive two new ciphers are presented: ten-round Cobra-H64, and twelve-round Cobra-H128. The designed ciphers operate efficiently with different plaintext lengths, 64 and 128-bit, for Cobra-H64 and Cobra-H128, respectively. Both of them use very simple key scheduling that defines high performance, especially in the case of frequent key refreshing. A novel feature of Cobra-H64 and Cobra-H128 is the use of the Switchable Operations which prevent the weak keys. The offered high-level security strength does not sacrifice the implementation performance, of both ciphers. Architecture, design and hardware implementation of the two ciphers are presented. The synthesis results for both FPGA and ASIC implementations prove that Cobra-H64 and Cobra-H128 are very flexible and powerful new ciphers, especially for high-speed networks. The achieved hardware performance and the implementation area cost of Cobra-H64 and Cobra-H128 are compared with other ciphers, used in security layers of wireless protocols (Bluetooth, WAP, OMA, UMTS and IEEE 802.11). From these comparisons it is proven that the two proposed are flexible new ciphers with better performance in most of the cases, suitable for wireless communications networks of present and future. <s> BIB042 </s> Mobile Systems Development - A literature review <s> PERSPECTIVES <s> Intrusion detection has, over the last few years, assumed paramount importance within the broad realm of network security and it has significant impact on wireless ad hoc networks. These networks do not have an underlying infrastructure and the network topology constantly changes. The inherently vulnerable characteristics of wireless ad hoc networks make them susceptible to attacks, and it may be difficult to control before any prevention works out. Secondly, with so much advancement in hacking, if attackers use sophisticated technology, they will eventually succeed in infiltrating the system. This makes it important to constantly or periodically monitor what is taking place on a system and look for suspicious behavior. Intrusion detection systems (IDS)monitor audit data, look for intrusions to the system, and initiate a proper response. In this paper, we present a method for determining critical path that use the distributed security scheme to find out the malicious node. The nodes with the help of the critical links will find out the malicious node using distributed security scheme and inform all the nodes about malicious node. The simulation results describe the details of the critical path test. <s> BIB043
The relevance of the different discourses within the existing research on mobility has been considered by applying a systems development lens. We end up with 105 articles revealing four perspectives (first level categories) in total covering 8 different areas (second level concepts) of the literature on mobile systems development. The reviewed contributions and their distribution on perspectives and areas are shown in Table 1 ; numbers in square brackets indicate the amount of contributions within that area. 2001; BIB010     Ahlström, Berg et al. 2002; Andreasson, Axelsson et al. 2002; BIB017     BIB024 Andersson, Wridell et al. 2004; BIB031 BIB032     BIB033  Wireless communications [18] BIB003 BIB004 BIB008  BIB011 BIB025  BIB026   BIB027  BIB034 BIB035     Architecture [17] BIB001 BIB002 BIB007 BIB009 BIB012 BIB013  BIB014   BIB018  BIB028  BIB036 BIB037 BIB038 Technology Security [18] BIB005 BIB006 BIB015 BIB016 BIB019 BIB020 BIB021 BIB022 BIB023 BIB029  BIB030 BIB039  BIB043 BIB040 BIB041 BIB042 Application Application We suggest that the four perspectives all have a role to play or influence the practice of mobile systems development. It should be noted that in the following presentation only a representative subset of the articles are used.