QISM：一种基于中间件和服务的无线传感器网络主动QoS体系

提出了一种基于中间件、面向服务的无线传感器网络主动QoS体系QISM,对其设计思想、体系结构、关键模块和工作过程进行了论述.基于应用和网络反馈协商的动态调节机制,基于中间件和服务发布与订阅的体系结构,以及基于Topic和功能域的表达方式,是QISM的重要特点.QISM通过对应用和网络的动态调节,使网络最大限度的支持应用,应用最大程度的适应网络,从而更好地保证了应用的完成,延长了网络生命期.针对典型场景的仿真结果表明,QISM机制具有良好的QoS控制能力和灵活性,支持复杂应用,且同网络结构形式无关.     

QISM 一种基于中间件和服服的无线传感器网络主动QoS体系

提出了一种基于中间件、面向服务的无线传感器网络主动QoS体系QISM，对其设计思想、体系结构、关键模块和工作过程进行了论述．基于应用和网络反馈协商的动态调节机制，基于中间件和服务发布与订阅的体系结构，以及基于Topic和功能域的表达方式，是QISM的重要特点．QISM通过对应用和网络的动态调节，使网络最大限度的支持应用，应用最大程度的适应网络，从而更好地保证了应用的完成，延长了网络生命期．针对典型场景的仿真结果表明，QISM机制具有良好的QoS控制能力和灵活性，支持复杂应用，且同网络结构形式无关。     

无线传感器网络中间件研究进展

无线传感器网络作为一种新兴的技术,受到了学术界和工业界的广泛关注.然而随着传感器网络及其应用的发展,系统的复杂性也随之增加,与传统网络相比无限传感器网络又具有其独特的特征,使得无线传感器网络的程序开发变得更加困难.中间件提供了一个编程抽象,方便了应用程序的开发,缩减了应用程序和底层设备的间隙.针对无线传感器网络的特点,分析了无线传感器网络中间件设计面临的问题,对有关设计方法进行了分类评述,并对几种典型中间件进行了比较,最后从通信范式、QoS支持和安全等方面提出了一些改进思路.     

无线传感器网络QoS仿真与研究

无线传感器网络在军事和民用领域均具有广阔的应用前景,但由于传感器节点资源的限制,网络能否满足在实际应用中的QoS要求是一个重要问题。本文对无线传感器网络的主要QoS指标进行了介绍,并分别从能量效率、丢包率、吞吐量和传输时延等主要QoS指标对三种典型拓扑结构的无线传感器网络进行了分析;实现了基于NS2的无线传感器网络通用仿真平台,借助此平台对典型拓扑结构的传感器网络主要QoS指标进行了仿真验证和分析,得到了不同拓扑结构对无线传感器网络QoS指标的影响程度。     

无线传感器网络中间件技术研究综述

无线传感器网络在受到广泛应用与关注的同时,由于网络复杂度及网络应用的增加,普遍存在缺乏统一开放接口的问题。针对无线传感器网络结构及特点,介绍无线传感器网络中间件技术概念,在全面分析中间件面临的问题与挑战的基础上,比较几种不同设计方法,并且通过典型实例在几个重要性能参数方面进行了对比。最后在中间件QoS机制模型方面提出了一种改进方法。     

一种基于服务中间件的无线传感器网络多维QoS评价机制

面向无线传感器网络的需求,对基于服务中间件的QoS保障机制进行探讨。聚焦QoS评价问题,提出一个基于多维云的QoS评价算法,对任务进行定量评价,使中间件能根据评价结果进行适当调度;同时,针对云参数经验性设置的弱点,利用获益驱动函数进行修正,提高评价的准确性。实验表明,算法能有效提高任务执行效率和延长网络生命周期。     

基于ANTS的主动路由支撑框架的设计与实现

在主动网工具包ANTS的基础上实现了一个QCAR原型系统,通过拓展ANTS的框架结构使其支持主动路由服务和沿途的QoS保障,并在该框架的基础上给出了一个主动路由的应用TraceRtApplication,通过具体的主动路由示例程序的实施,说明了如何在QCAR系统上开发新的应用。该文的研究和实现证明,与传统网络相比,在主动网基础上通过向网络中注入用户定制的、面向应用的路由需求代码,可以方便地实现生动路由定制和QoS保障。     

基于主动网络的RSVP体系结构设计

IP网络新的应用对网络的服务质量(QoS)提出了新的不同的要求,因此必须在现有的“尽力服务”机制的基础上提供服务质量管理机制。在对QoS进行分析的基础上,提出了一种新的QoS体系结构,即基于主动网络的QoS体系结构,并结合IntServ QoS模型,提出了支持RSVP协议动态部署的主动节点的模型。     

无线传感器网络QoS路由研究进展*

传统网络中的服务质量(quality of service,QoS)路由协议很难直接有效地应用到无线传感器网络中,因此人们针对无线传感器网络提出了一些新的QoS路由协议。首先探讨了无线传感器网络中QoS路由协议的一些特点,分析了设计QoS路由协议所面临的挑战;然后着重分析了当前提出的一些QoS路由协议的QoS机制、特点以及优缺点,并对这些路由协议进行了分类和比较;最后总结了QoS路由协议未来的研究策略和发展趋势。     

无线多媒体传感器网络的QoS问题研究

无线多媒体传感器网络（WMSNs）是在传统无线传感器网络（WSNs）基础上发展起来的具有音频、视频、图像等多媒体信息感知功能的新型传感器网络．具有广阔的发展前景。WMSNs感知媒体丰富、数据量大和处理任务复杂等显著特点,使其QoS问题的研究极具挑战性。该文分析了WMSNs的QoS需求,并从MAC层和网络层讨论了这一领域的国内外研究现状。最后对QoS亟待解决的问题作了总结。     

Efficient allocation of resources in multiple heterogeneous Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are useful for a wide range of applications, from different domains. Recently, new features and design trends have emerged in the WSN field, making those networks appealing not only to the scientific community but also to the industry. One such trend is the running different applications on heterogeneous sensor nodes deployed in multiple WSNs in order to better exploit the expensive physical network infrastructure. Another trend deals with the capability of accessing sensor generated data from the Web, fitting WSNs in novel paradigms of Internet of Things (IoT) and Web of Things (WoT). Using well-known and broadly accepted Web standards and protocols enables the interoperation of heterogeneous WSNs and the integration of their data with other Web resources, in order to provide the final user with value-added information and applications. Such emergent scenarios where multiple networks and applications interoperate to meet high level requirements of the user will pose several changes in the design and execution of WSN systems. One of these challenges regards the fact that applications will probably compete for the resources offered by the underlying sensor nodes through the Web. Thus, it is crucial to design mechanisms that effectively and dynamically coordinate the sharing of the available resources to optimize resource utilization while meeting application requirements. However, it is likely that Quality of Service (QoS) requirements of different applications cannot be simultaneously met, while efficiently sharing the scarce networks resources, thus bringing the need of managing an inherent tradeoff. In this paper, we argue that a middleware platform is required to manage heterogeneous WSNs and efficiently share their resources while satisfying user needs in the emergent scenarios of WoT. Such middleware should provide several services to control running application as well as to distribute and coordinate nodes in the execution of submitted sensing tasks in an energy-efficient and QoS-enabled way. As part of the middleware provided services we present the Resource Allocation in Heterogeneous WSNs (SACHSEN) algorithm. SACHSEN is a new resource allocation heuristic for systems composed of heterogeneous WSNs that effectively deals with the tradeoff between possibly conflicting QoS requirements and exploits heterogeneity of multiple WSNs.     

A survey on service-oriented middleware for wireless sensor networks

Wireless sensor networks (WSN) are used for many applications such as environmental monitoring, infrastructure security, healthcare applications, and traffic control. The design and development of such applications must address many challenges dictated by WSN characteristics on one hand and the targeted applications on the other. One of the emerging approaches used for relaxing these challenges is using service-oriented middleware (SOM). Service-oriented computing, in general, aims to make services available and easily accessible through standardized models and protocols without having to worry about the underlying infrastructures, development models, or implementation details. SOM could play an important role in facilitating the design, development, and implementation of service-oriented systems. This will help achieve interoperability, loose coupling, and heterogeneity support. Furthermore, SOM approaches will provision non-functional requirements like scalability, reliability, flexibility, and Quality of Service (QoS) assurance. This paper surveys the current work in SOM and the trends and challenges to be addressed when designing and developing these solutions for WSN.     

Supporting end-to-end quality of service properties in OMG data distribution service publish/subscribe middleware over wide area networks

Assuring end-to-end quality-of-service (QoS) in distributed real-time and embedded (DRE) systems is hard due to the heterogeneity and scale of communication networks, transient behavior, and the lack of mechanisms that holistically schedule different resources end-to-end. This paper makes two contributions to research focusing on overcoming these problems in the context of wide area network (WAN)-based DRE applications that use the OMG Data Distribution Service (DDS) QoS-enabled publish/subscribe middleware. First, it provides an analytical approach to bound the delays incurred along the critical path in a typical DDS-based publish/subscribe stream, which helps ensure predictable end-to-end delays. Second, it presents the design and evaluation of a policy-driven framework called Velox. Velox combines multi-layer, standards-based technologies—including the OMG DDS and IP DiffServ—to support end-to-end QoS in heterogeneous networks and shield applications from the details of network QoS mechanisms by specifying per-flow QoS requirements. The results of empirical tests conducted using Velox show how combining DDS with DiffServ enhances the schedulability and predictability of DRE applications, improves data delivery over heterogeneous IP networks, and provides network-level differentiated performance.     

Quality-of-service trade-off analysis for wireless sensor networks

Quality of Service (QoS) support for wireless sensor networks (WSN) is a fairly new topic that is gaining more and more interest. This paper introduces a method for determining the node configurations of a WSN such that application-level QoS constraints are met. This is a complex task, since the search space is typically extremely large. The method is based on a recent algebraic approach to Pareto analysis, that we use to reason about QoS trade-offs. It features an algorithm that keeps the working set of possible configurations small, by analysing parts of the network in a modular fashion, and meanwhile discarding configurations that are inferior to other configurations. Furthermore, we give WSN models for two different applications, spatial mapping and target tracking, in which QoS trade-offs are made explicit. Test results for these applications and a heterogeneous WSN combining these two applications show that the models are accurate and that the method is scalable and thus practically usable for WSN, even with large numbers of nodes. Details are given on how to efficiently implement the algorithm.     

基于AOP的QoS中间件自适应机制研究

异构动态实时系统中复杂的应用层QoS参数分解为多个操作系统和网络支持的QoS参数,并映射为操作系统和网络无法提供的实现机制,QoS中间件需要实现这些机制。本文首先讨论了QoS中间件的体系结构,进一步给出了一种基于面向方面的编程技术AOP的QoS中间件自适应机制。采用这种机制,通过间接增加一个额外层,将服务中的所有组件编织到一个自适应方面里。     

��DDS: A Middleware for Real-time Wireless Embedded Systems

A Real-Time Wireless Distributed Embedded System (RTWDES) is formed by a large quantity of small devices with certain computing power, wireless communication and sensing/actuators capabilities. These types of networks have become popular as they have been developed for applications which can carry out a vast quantity of tasks, including home and building monitoring, object tracking, precision agriculture, military applications, disaster recovery, industry applications, among others. For this type of applications a middleware is used in software systems to bridge the gap between the application and the underlying operating system and networks. As a result, a middleware system can facilitate the development of applications and is designed to provide common services to the applications. The development of a middleware for sensor networks presents several challenges due to the limited computational resources and energy of the different nodes. This work is related with the design, implementation and test of a micro middleware for RTWDES; the proposal incorporates characteristics of a message oriented middleware thus allowing the applications to communicate by employing the publish/subscribe model. Experimental evaluation shows that the proposed middleware provides a stable and timely service to support different Quality of Service (QoS) levels.     

Supporting SIP-based end-to-end Data Distribution Service QoS in WANs

Assuring end-to-end QoS in enterprise distributed real-time and embedded (DRE) systems is hard due to the heterogeneity and transient behavior of communication networks, the lack of integrated mechanisms that schedule communication and computing resources holistically, and the scalability limits of IP multicast in wide-area networks (WANs). This paper makes three contributions to research on overcoming these problems in the context of enterprise DRE systems that use the OMG Data Distribution Service (DDS) quality-of-service (QoS)-enabled publish/subscribe (pub/sub) middleware over WANs. First, it codifies the limitations of conventional DDS implementations deployed over WANs. Second, it describes a middleware component called Proxy DDS that bridges multiple, isolated DDS domains deployed over WANs. Third, it describes the NetQSIP framework that combines multi-layer, standards-based technologies including the OMG-DDS, Session Initiation Protocol (SIP), and IP DiffServ to support end-to-end QoS in a WAN and shield pub/sub applications from tedious and error-prone details of network QoS mechanisms. The results of experiments using Proxy DDS and NetQSIP show how combining DDS with SIP in DiffServ networks significantly improves dynamic resource reservation in WANs and provides effective end-to-end QoS management.     

POSAML: A visual modeling language for middleware provisioning

Next generation distributed applications are often hosted on heterogeneous platforms including different kinds of middleware. Due to the applications’ growing functional complexity and their multiple quality of service (QoS) requirements, system developers are increasingly facing a substantial number of middleware provisioning challenges, which include configuring, optimizing and validating the middleware platforms for QoS properties. Traditional techniques for middleware provisioning tend to use non-intuitive, low-level and technology-specific approaches, which are tedious, error prone, and non-reusable across different technologies. Quite often the middleware provisioning activities are carried out by different actors without much interaction among them, which results in an iterative trial-and-error process to provisioning. Higher level abstractions, particularly those that use visual models, are effective in addressing these challenges. This paper describes the design of a visual modeling language called POSAML (pattern-oriented software architecture modeling language) and associated tools that provide an intuitive, higher level and unified framework for provisioning middleware platforms. POSAML provides visual modeling capabilities for middleware-independent configurations and optimizations while enabling automated middleware-specific validation of system QoS properties.