A Framework for Adaptive UbiComp Applications Based on the Jack-in-the-Net Architecture

The Jack-in-the-Net Architecture (Ja-Net) that we present in this paper provides a unique and promising approach to design ubiquitous computing applications that can scale, self-organize, and adapt to short- and long-term changes in network conditions and user preferences. In Ja-Net, network applications are implemented by a group of distributed, autonomous entities called the cyber-entities. Each cyber-entity implements a function component related to its service and follows simple behavior rules (such as migration, replication, energy exchange, death, and relationship establishment with other cyber-entities). They form organizations or communities by establishing and learning useful relationships with a number of other cyber-entities and collectively provide higher level services through interactions among them. Consequently, desirable services and characteristics emerge in network applications through autonomous and self-organizing interactions among cyber-entities (service emergence). In this paper, we discuss the design and implementation of Ja-Net platform software that achieves dynamic and adaptive provision of network applications through service emergence. We also built an application for Ja-Net that features service emergence and we empirically verified that the application can adapt itself to user preferences.     

Motivations, Design and Business Models of Wireless Community Networks

In this paper we provide an integrated presentation of applications, technologies and business models for wireless community network together with design considerations and examples. An overview is given of the state-of-the-affairs of wireless community networks. Driving forces and stakeholders of the projects and the applications and services will be presented for some carefully selected cases. We suggest a design methodology and illustrate its application to an ongoing digital city project in Hungary. Relevant business models are also analyzed.     

Middleware technologies for cloud of things: a survey

The next wave of communication and applications will rely on new services provided by the Internet of Things which is becoming an important aspect in human and machines future. IoT services are a key solution for providing smart environments in homes, buildings, and cities. In the era of massive number of connected things and objects with high growth rate, several challenges have been raised, such as management, aggregation, and storage for big produced data. To address some of these issues, cloud computing emerged to the IoT as Cloud of Things (CoT), which provides virtually unlimited cloud services to enhance the large-scale IoT platforms. There are several factors to be considered in the design and implementation of a CoT platform. One of the most important and challenging problems is the heterogeneity of different objects. This problem can be addressed by deploying a suitable “middleware” which sits between things and applications as a reliable platform for communication among things with different interfaces, operating systems, and architectures. The main aim of this paper is to study the middleware technologies for CoT. Toward this end, we first present the main features and characteristics of middlewares. Next, we study different architecture styles and service domains. Then, we present several middlewares that are suitable for CoT-based platforms and finally, a list of current challenges and issues in the design of CoT-based middlewares is discussed.     

Security in vehicular ad hoc networks [security in mobile ad hoc]

Vehicular communication networking is a promising approach to facilitating road safety, traffic management, and infotainment dissemination for drivers and passengers. One of the ultimate goals in the design of such networking is to resist various malicious abuses and security attacks. In this article we first review the current standardization process, which covers the methods of providing security services and preserving driver privacy for wireless access in vehicular environments (WAVE) applications. We then address two fundamental issues, certificate revocation and conditional privacy preservation, for making the standards practical. In addition, a suite of novel security mechanisms are introduced for achieving secure certificate revocation and conditional privacy preservation, which are considered among the most challenging design objectives in vehicular ad hoc networks.     

Intelligence in ATM terminals

In this paper we propose to migrate the intelligence for telecommunication services from the network into the terminals. In the first three sections we elaborate on the approach taken. The descending cost of processing equipment and the increased flexibility offered by ATM networks open new perspectives for the terminal business. In addition, only limited services will be offered by early ATM networks. Terminal-based intelligence may overcome this initial gap. The physical configuration of such a terminal is presented in Section 4. In Section 5 the functional configuration of the terminal is proposed. The control module realizes a generic platform for the execution of telecommunication applications. This platform gives access both to local peripherals and to the telecommunication services offered by the network. The top layer consists of the telecommunication applications. In Section 6 a number of these applications are discussed. The remote execution application is of special interest since it gives remote access to telecommunication applications hosted on other IATs, so enlarging the capabilities of the local IAT.     

Blockchain-based continuous data integrity checking protocol with zero-knowledge privacy protection

The cloud computing technology has emerged, developed, and matured in recent years, consequently commercializing remote outsourcing storage services. An increasing number of companies and individuals have chosen the cloud to store their data. However, accidents, such as cloud server downtime, cloud data loss, and accidental deletion, are serious issues for some applications that need to run around the clock. For some mission and business-critical applications, the continuous availability of outsourcing storage services is also necessary to protect users' outsourced data during downtime. Nevertheless, ensuring the continuous availability of data in public cloud data integrity auditing protocols leads to data privacy issues because auditors can obtain the data content of users by a sufficient number of storage proofs. Therefore, protecting data privacy is a burning issue. In addition, existing data integrity auditing schemes that rely on semi-trusted third-party auditors have several security problems, including single points of failure and performance bottlenecks. To deal with these issues, we propose herein a blockchain-based continuous data integrity checking protocol with zero-knowledge privacy protection. We realize a concrete construction by using a verifiable delay function with high efficiency and proof of retrievability, and prove the security of the proposal in a random oracle model. The proposed construction supports dynamic updates for the outsourced data. We also design smart contracts to ensure fairness among the parties involved. Finally, we implement the protocols, and the experimental results demonstrate the efficiency of the proposed protocol.     

Optimal provisioning for virtual network request in cloud-based data centers

Today applications and services are migrating to a cloud-computing-based paradigm in which the users access the applications and services hosted in data centers, by using thin-clients on the user terminal device. These applications/services are typically hosted and run on virtual machines in interconnected data centers. Different applications from the same user may need to access and change shared data or information. Thus, we may abstract the applications from same user as a virtual network (VN). For better performance and efficiency, it is critical that the VN request be accommodated with optimal provisioning under the current resource state of data centers. In this paper, for addressing the issue of how to design an optimal provisioning scheme for the VN request such that the total revenue of is maximized, we first develop a framework for the optimal provisioning of VN request by using mixed integer programming. Since the optimal provisioning problem is NP-hard, we also propose a genetic algorithm?Cbased heuristic algorithm for addressing the problem of optimal provisioning for VN with unsplittable flow and optimal provisioning for VN with splittable flow problems. We demonstrate the effectiveness of our approach in improving the total revenue by conducting extensive simulations on different networks.     

On the inclusion of geographic information systems (GIS) in global navigation satellite systems (GNSS)

The latest innovation of the global navigation satellite systems (GNSS) technologies plays an important role in improving the quality and safety of modern life. Most of the applications evolved from the integration between GNSS, geographical information systems (GIS) and wireless communications and networking (WCN) systems. The wide spread applications that are using these technologies include: the automatic vehicle location (AVL), tracking systems, navigation systems, pedestrian navigation systems, intelligent transportation systems, precise positioning, and emergency callers, among others. The location‐based services (LBS) are possible only by the combination of GNSS, GIS and WCN. The growing need for commercial LBS has forced cellular‐phone and network manufacturers to concentrate on positioning solutions, which are even more precise than the regulatory mandates for positioning of emergency callers and other user services and applications. In this paper, we will present a literature review of the GNSS, the three satellite systems GPS, GLONASS and Galileo, which are aimed to support GNSS services, and a comparison between them and their role in creating a GIS. Copyright © 2006 John Wiley & Sons, Ltd.     

Orchestration in Web Services and Real-Time Communications

Web services orchestration is now being adopted for the coordination of real-time communications services, including telephony, video and multimedia communications. But do these communications services integrate into workflows in the same way as Web services in the data environment, and are orchestration mechanisms for Web services sufficient for the needs of workflows that involve real-time communications? In this article we explore these questions by taking a look at three approaches to orchestrating workflows: Business Process Execution Language (BPEL), Call Control extensible Markup Language (CCXML), and State Chart extensible Markup Language (SCXML). Through an analysis of these languages, we find that although there are similarities between BPEL as a Web services orchestration language and CCXML/SCXML as orchestration languages for telecom applications, certain key differences, namely procedural vs. event-based representation and coarse vs. fine task granularity, make it more suitable to use these two types of languages together rather than having one replace the other in converged voice-data applications.     

Design of a DVB-T/H COFDM Receiver for Portable Video Applications [Topics in Circuits for Communications]

Mobile video services have generated a lot of interest recently. To reach a cost-effective solution, design trade-offs among system performance, hardware complexity, and power consumption must be considered in the early design phase of such applications. In this article, we present a system overview, simulation platform, and hardware design of a DVB-T/H baseband receiver. Starting with a design platform, several algorithms on both inner and outer receivers are developed to meet target system performance under different channels. Then, system architecture and related key modules are explored, taking into account both silicon area and power consumption. Finally, several design issues related to the integration of the proposed DVB-T/H inner and outer receivers are addressed.     

Using MDA to develop Component and Aspect Based Applications

Distributed systems are complex and, consequently, their design and development is not an easy task. In order to manage such complexity, it is not enough the use of the appropriate software technologies. Additionally, software developers need to differentiate clearly the several concepts used at different levels of the development (application domain, application architecture, implementation language and platform, etc.). This paper proposes the use of MDA in the development of CAM/DAOP applications, where CAM/DAOP is a component-aspect model and platform that we have developed for the construction of distributed applications. The main goal of this paper is to describe the process we followed to identify and separate the entities that live at different levels, and the transformations among them.     

VCMIA: A Novel Architecture for Integrating Vehicular Cyber-Physical Systems and Mobile Cloud Computing

The advances in wireless communication technologies, vehicular networks and cloud computing boost a growing interest in the design, development and deployment of Vehicular Cyber-Physical Systems (VCPS) for some emerging applications, which leads to an increasing demand on connecting Mobile Cloud Computing (MCC) users to VCPS for accessing the richer applications and services. In this paper, we first identify the key requirements of designing an efficient and flexible architecture for integrating MCC and VCPS. Based on the requirements, we design a VCPS and MCC Integration Architecture (VCMIA), which provides mobile services for potential users such as drivers and passengers to access mobile traffic cloud. Then, we ana- lyze two crucial cloud-supported components: GIS with traffic-aware capability and cloud-supported dynamic vehicle routing. Finally, we select Vehicle Maintenance Services (VMS) as an application scenario to carry out the validation. The proposed VCMIA can provide the flexibility for enabling diverse applications.     

Web Service Based Mobile Worker Supporting System for Construction Industry Applications

More and more construction companies have recognized the potential importance and transformative impact of mobile applications and are planning to build their own mobile information system. Current and emerging developments in web services and agent technologies will have a radical impact on future mobile management system of construction sites. This paper first analyzes the essential requirement of construction mobile information system, followed by special requirements deemed essential to provide high efficient and secure system. Based on this requirement analysis, we present the mobile information system architecture. In the next section, we develop the demonstration prototype this solution. And in the last section, we conclude the paper.     

Efficient scheduling algorithms for mixed services in wireless OFDMA system

Orthogonal Frequency Division Multiple Access (OFDMA) is an attracting system for combating the frequency selective fading. It’s widely considered as a promising candidate modulation and access scheme for next generation mobile communication systems. However, the explosive growth of multimedia applications raises higher performance requirements for Radio Resource Management (RRM) in OFDMA system. In particular, limited bandwidth and fierce resource competition impose a challenging issue on the design of packet scheduler. In this paper, we propose two scheduling algorithms applicable to mixed services (i.e., real-time and non-real-time services), that is QoS-oriented Dynamic Threshold Control (DTC) algorithm and fairness-oriented Fairness Aware and QoS Aware (FAQA) algorithm. These two algorithms are both composed of two stages, i.e., initial subcarrier allocation and subcarrier reallocation. For the DTC algorithm, in the stage of initial subcarrier allocation, based on the different metrics to weigh QoS between both services, we design a unique scheduling strategy for each type of service. A dynamic threshold is adopted to help users quickly recover from starvation, so that any one user in system can escape from severely degraded QoS. In the stage of subcarrier reallocation, we will reallocate the surplus subcarriers from the buffer-empty users to the buffer-nonempty users so as to increase spectrum efficiency. For FAQA algorithm, in the stage of initial subcarrier allocation, for the purpose of achieving Proportional Fairness (PF) with lower complexity, we deduce a simple scheduling strategy satisfying PF criterion by means of Greedy algorithm. In the stage of subcarrier reallocation, in order to increase the number of users satisfying QoS requirements, we’ll reallocate the surplus subcarriers from the QoS-satisfied users to the QoS-unsatisfied users. Simulation results demonstrate that, on one hand, the DTC algorithm not only guarantees the quality of both services, but also increases the spectrum efficiency; on the other hand, the FAQA algorithm well maintains the fairness among users, and increases the QoS satisfaction degree at the same time.     

An intelligent-agent architecture for flexible service integration on the web

A plethora of information and services is available on the World Wide Web; the challenge has now become to enable the interoperation of these services in the context of high-quality, integrated applications, providing personalized value-added services to the end user. TaMeX is a software framework that supports the development of intelligent multiagent applications, integrating services of existing web applications. The TaMeX applications rely on a set of specifications of the domain model, the integration workflow, their semantic constraints, the end-user profiles, and the services of the existing web applications; all these models are declaratively represented in the XML-based TaMeX integration-specification language. At run-time, the TaMeX agents use these models to flexibly interact with the end users, monitor and control the execution of the underlying applications' services and coordinate the information exchange among them, and to collaborate with each other to react to failures and effectively accomplish the desired user request. In this paper, we describe the TaMeX framework and we illustrate its capabilities with an integrated book-finding application as a case study.     

Design of RF transceivers for wireless sensor networks in hazardous applications

Wireless sensor networks (WSN) have a great prospect in many applications, among which the monitoring of hazardous environments is becoming more and more important. The basic requirements of WSN design are low cost and low power consumption, and then a low-power system-on-chip implementation is an optimal solution for WSN nodes. However, the radio-frequency (RF) part of a node chip is usually power hungry and difficult to fully integrate, so many previous works have focused on the design of RF transceivers for WSN. Specifically, for hazardous applications, the communication range is required to be long enough to protect human from harmful environments. So a long effective communication distance is also necessary for WSN transceivers in hazardous applications. In this paper, we give a survey and a classification of WSN transceivers. Furthermore, we analyze the advantages and disadvantages of three main WSN transceivers, i.e. on-off keying transceivers, ultra-wide band transceivers, and frequency shift keying transceivers; and then find out the one most suitable for hazardous applications.     

WComp middleware for ubiquitous computing: Aspects and composite event-based Web services

After a survey of the specific features of ubiquitous computing applications and corresponding middleware requirements, we list the various paradigms used in the main middlewares for ubiquitous computing in the literature. We underline the lack of works introducing the use of the concept of Aspects in middleware dedicated to ubiquitous computing, in spite of them being used for middleware improvement in other domains. Then, we introduce our WComp middleware model, which federates three main paradigms: event-based Web services, a lightweight component-based approach to design dynamic composite services, and an adaptation approach using the original concept called Aspect of Assembly. These paradigms lead to two ways to dynamically design ubiquitous computing applications. The first implements a classical component-based compositional approach to design higher-level composite Web Services and then allow to increment the graph of cooperating services for the applications. This approach is well suited to design the applications in a known, common, and usual context. The second way uses a compositional approach for adaptation using Aspect of Assembly, particularly well-suited to tune a set of composite services in reaction to a particular variation of the context or changing preferences of the users. Having detailed Aspect of Assembly concept, we finally comment on results indicating the expressiveness and the performance of such an approach, showing empirically that principles of aspects and program integration can be used to facilitate the design of adaptive applications.     

基于Net-SNMP的多业务网管代理扩展的设计与实现

随着网络技术的标准化和基于网络的应用不断丰富和增多,网络管理的研究方向越来越侧重于对业务的管理,研究和设计统一的综合业务网管系统日益显示出重要性。被管业务主要是通过代理机制同网管系统交互以实现接收来自网管系统的查询请求以及告警事件的主动上报,而在实际系统中业务种类众多,功能机构也各不相同,因此设计简单可靠、低成本、扩展性高的代理扩展方法是保证综合业务网管系统高效可靠的一个重要元素。文章提出了一种基于Net-SNMP的多业务网管代理的设计与实现方法:在一个具体的网络管理节点下利用Net-SNMP作为Master Agent,而将subagent嵌入到具体的业务系统,subagent只同master agent通信,实现业务agent与网管系统的间接通信。实际工程结果表明:该方法对设计和开发综合业务网管系统切实可用,并能极大提高网管系统中管理设备和被管业务的动态扩展性。     

Introducing new Internet services: why and how

Active networks permit applications to inject programs into the nodes of local and, more important, wide area networks. This supports faster service innovation by making it easier to deploy new network services. In this article, we discuss both the potential impact of active network services on applications and how such services can be built and deployed. We explore the impact by suggesting sample uses and arguing how such uses would improve application performance. We explore the design of active networks by presenting a novel architecture, ANTS (active network transport system), that adds extensibility at the network layer and allows for incremental deployment of active nodes within the Internet. In doing so, ANTS tackles the challenges of ensuring that the flexibility offered by active networks does not adversely impact performance or security. Finally, we demonstrate how a new network service may be expressed in ANTS     

WIRELESS BROADBAND ACCESS: WIMAX AND BEYOND - A Secure and Service-Oriented Network Control Framework for WiMAX Networks

WiMAX, worldwide interoperability for microwave access, is an emerging wireless communication system that can provide broadband access with large-scale coverage. As a cost-effective solution, multihop communication is becoming more and more important to WiMAX systems. To successfully deploy multihop WiMAX networks, security is one of the major challenges that must be addressed. Another crucial issue is how to support different services and applications in WiMAX networks. Since WiMAX is a relatively new standard, very little work has been presented in the literature. In this article we propose a secure and service-oriented network control framework for WiMAX networks. In the design of this framework we consider both the security requirements of the communications and the requirements of potential WiMAX applications that have not been fully addressed previously in the network layer design. The proposed framework consists of two basic components: a service-aware control framework and a unified routing scheme. Besides the design of the framework, we further study a number of key enabling technologies that are important to a practical WiMAX network. Our study can provide a guideline for the design of a more secure and practical WiMAX network