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A Real-Time-Enabled, Blackboard-Based, publish/subscribe Architecture for Wireless Sensor Nodes

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Wireless Sensor Network 2010年第8期2卷 612-628页

作者： Bjorn Stelte 不详

Wireless sensor network nodes have only limited resources concerning memory and battery life-time. Mem- ory can be efficiently used by sharing data, and the life-time of a battery can be extended, when the node has long power saving sleep-phases. We propose a publish/subscribe architecture that achieves these two aims. The results of our work are of great interest for sensor application developers, giving them now the opportu- nity to use our architecture for sharing data among different applications on the node as well as the different layers of the operating system. We introduce a blackboard which is used for centrally storing published val- ues, like measured data from a monitored sensor. This makes it possible to share stored data without monitoring the sensors once again, which is advantageously concerning power consumption, memory space, and reaction time. Beside the proposed publish/subscribe method for sensor nodes with its notification possibili- ties, our architecture fulfills also real-time requirements. We show how the well-known sensor operating system MANTIS OS can be extended by a real-time enabled, blackboard-based publish/subscribe architect- ture. This architecture and first of all its implementation is of special interest for cross layer optimization of sensor applications. Cross-layer approaches benefit from our architecture because the available implementa- tion can be used as an efficient framework for central storing and managing of shared values.

关键词： Blackboard Real-Time publish/subscribe Architecture Wireless Sensor Network

Embedding Authentication &Authorization in Discovery Protocols for Standard Based publish/subscribe Middleware: A Performance Evaluation

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Communications and Network 2011年第1期3卷 39-49页

作者： Fabrizio Ronci Marco Listanti 不详

Standard based Pub/Sub middleware, such as OMG Data Distribution Service (DDS), could assume a key role in supporting computer communications requiring continuous state information updating, deterministic deadline to data delivering and real time information adjourning. This kind of capability could be well ex-ploited by Peer-To-Peer (P2P) systems, Internet-wide as long as private ones, like in Public Safety or Civil Protection Communication Systems;but Pub/Sub specifications, and DDS/RTPS (Real Time publish Sub-scribe) as well, usually do not provide Authentication & Authorization (AA) mechanisms. In the present work two important novelties are assessed: a possible scheme to implement AA in DDS/RTPS networks and a time performance evaluation study about embedded Authentication in RTPS.

关键词： Middleware publish/subscribe Data Distribution Service Authentication Authorization

基于XML的广域网publish/subscribe事件通知服务平台的设计和实现

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基于XML的广域网Publish/Subscribe事件通知服务平台的设计和实现

作者：李健民中国科学院研究生院（软件研究所）

学位级别：硕士

Internet技术的广泛应用和飞速发展，极大地改变了分布式系统的应用范围和规模，publish／subscribe通讯模型能够很好地适应部署在Internet上的大规模应用系统松散通讯和管理的需要，因此近些年来该方面的技术引起了广泛的关注。 ... 详细信息

Internet技术的广泛应用和飞速发展，极大地改变了分布式系统的应用范围和规模，publish／subscribe通讯模型能够很好地适应部署在Internet上的大规模应用系统松散通讯和管理的需要，因此近些年来该方面的技术引起了广泛的关注。但是，现有的实现平台集中在以固定的结构化的方式来表达通知信息，本文认为广域网上分布式服务最重要的一点是数据的自我表达能力，这样不依赖于具体数据格式的结构，使得整个系统的各个部分能够分别改进而互不影响。XML正是这样一种语言，它允许把文档的结构信息和文档数据本身编码在一起，而且XML已经成为Internet上信息交换标准。本文将探讨以XML作为描述语言的广域网publish／subscribe平台的实现。本文对publish／subscribe模式进行了概括性介绍，讨论了publish／subscribe系统的特征以及实现事件通知服务时的关键内容。在此之后，本文详细描述了基于XML的广域网publish／subscribe平台的设计和实现，并开发一个分布式股票信息交易系统对系统的有效性进行了验证。

关键词： publish/subscribe 事件通知服务 XML

Research of publish and subscribe Model Based on WS-Notification

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Journal of Software Engineering and Applications 2009年第4期2卷 295-300页

作者： Huilian FAN Guangpu ZEN Xianli LI 不详

WS-Notification bundle of standards, WS-BaseNotification, WS-Topics, and WS-BrokeredNotification, can be used as a general purpose publish/subscribe interface for Service Oriented Architectures. We provide an overview of the WS-Notification specification and describe a modified publish and subscribe model based on WS-Notification. The model is an adaptive policy-driven notification framework that can help enterprises to meet the flexibility and respon-siveness requirements of the enterprise. With the modified publish/subscribe model, information consumers can dy-namically and declaratively create and configure entities on their behalves to manage their distribution requirements.

关键词： WS-Notification publish/subscribe Notification Broker Service Notification Consumer Proxy Service

Toward high efficiency for content-based multiattribute event matching via hybrid methods

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Science China(Information Sciences) 2016年第2期59卷 201-216页

作者： Wenhao FAN Yuanan LIU Bihua TANG School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and Telecommunications

Event matching is a core in decoupled end-to-end communications, which are extensively applied to various areas. Event matching seeks the subscriptions that match a given event from a subscription set,however, this work becomes increasingly complicated in content-based multi-attribute scenarios, where events and subscriptions are formed in content, and described by multiple attributes. In addition, large-scale systems are easier to suffer from severe degradation in event matching performance. To this end, this paper presents a high-efficiency content-based multi-attribute event matching algorithm, called HEM(hybrid event matching),which is hybridized by 2 different methods. In HEM, the matching on each single attribute(called singleattribute matching) is processed by a triangle-based matching method or a direct matching method *** single-attribute matchings are sorted via a fast near-optimal algorithm, and each of them is carried out sequentially. In this manner, the searching space of event matching shrinks gradually, so that the searching performance is boosted along with the process of event matching. Experiments are conducted to evaluate HEM comprehensively, where it is observed that HEM outperforms 3 state-of-the-art counterparts(TAMA, H-TREE and REIN) in main criteria, such as event matching time, insertion time and deletion time. Moreover, the gap of performance between HEM and the counterparts enlarges with the increase of system scale.

关键词： event matching publish/subscribe data dissemination end-to-end communications interval search combinatorial optimization

Feverfew: a scalable coverage-based hybrid overlay for Internet-scale pub/sub networks

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Science China(Information Sciences) 2014年第5期57卷 51-64页

作者： MA XingKong WANG YiJie SUN WeiDong National Key Laboratory for Parallel and Distributed Processing School of ComputerNational University of Defense Technology

The publish/subscribe(pub/sub)paradigm is a popular communication model for data dissemination in large-scale distributed ***,scalability comes with a contradiction between the delivery latency and the memory *** one hand,constructing a separate overly per topic guarantees real-time dissemination,while the number of node degrees rapidly increases with the number of *** the other hand,maintaining a bounded number of connections per node guarantees small memory cost,while each message has to traverse a large number of uninterested nodes before reaching the *** this paper,we propose Feverfew,a coverage-based hybrid overlay that disseminates messages to all subscribers without uninterested nodes involved in,and increases the average number of node connections slowly with an increase in the number of subscribers and *** major novelty of Feverfew lies in its heuristic coverage mechanism implemented by combining a gossip-based sampling protocol with a probabilistic searching *** on the practical workload,our experimental results show that Feverfew significantly outperforms existing coverage-based overlay and DHT-based overlay in various dynamic network environments.

关键词： publish/subscribe coverage-based data dissemination topic-based gossip

MQTT and blockchain sharding:An approach to user-controlled data access with improved security and efficiency

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Blockchain(Research and Applications) 2023年第4期4卷 86-98页

作者： P.S.Akshatha S.M.Dilip Kumar Department of Computer Science and Engineering University of Visvesvaraya College of EngineeringBangalore UniversityBengaluruKarnataka 560056India

The rapid growth of the Internet of Things(IoT)has raised security concerns,including MQTT protocol-based applications that lack built-in security features and rely on resource-intensive Transport Layer Security(TLS)*** paper presents an approach that utilizes blockchain technology to enhance the security of MQTT communication while maintaining *** approach involves using blockchain sharding,which enables higher scalability,improved performance,and reduced computational overhead compared to traditional blockchain approaches,making it well-suited for resource-constrained IoT *** approach leverages Ethereum blockchain’s smart contract mechanism to ensure trust,accountability,and user ***,we introduce a shard-based consensus mechanism that enables improved security while minimizing computational *** also provide a user-controlled and secured algorithm using Proof-of-Access implementation to decentralize user access control to data stored in the blockchain *** proposed approach is analyzed for usability,including metrics such as bandwidth consumption,CPU usage,memory usage,delay,access time,storage time,and jitter,which are essential for IoT application *** analysis demonstrated that the approach reduces resource consumption,and the proposed system outperforms TLS and existing blockchain approaches in these metrics,regardless of the choice of the MQTT ***,thoroughly addressing future research directions,including issues and challenges,ensures careful consideration of potential advancements in this domain.

关键词： Blockchain Internet of Things MQTT publish/subscribe MQTT brokers HiveMQ Mosquitto EMQx Eclipse Sharding

An MID-Based Load Balancing Approach for Topic-Based Pub-Sub Overlay Construction

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Tsinghua Science and Technology 2011年第6期16卷 589-600页

作者： Ruisheng Shi Fuqiang Liu Yang Zhang Bo Cheng Junliang Chen State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Naval Academy of Armament Beijing 100073 China

A large proportion of Internet of Things （loT） applications are internally publish/subscribe in nature, and traditional architecture cannot support them efficiently and flexibly. In essence, supporting efficient publish/subscribe systems requires data-oriented naming and efficient multicast. Since deployment of native IP-based multicast has failed, overlay-based multicast has become the practical choice. Since load balancing between heterogeneous nodes is an important issue, designing an optimal load balancing overlay net- work for publish/subscribe systems is a necessary endeavor. This study focuses on the optimal load balancing overlay design problem for topic-based publish/subscribe systems in a heterogeneous environment （in terms of node processing power, bandwidth, and reachability）. The Minimum Idle Degree （MID） model is introduced to capture the heterogeneity of overlay nodes. Based on the MID model, new node load measures are defined that can accommodate heterogeneous server capacities and capture the node load in publish/subscribe systems more accurately than traditional measures. A new optimization problem, Maximum Minimum Idle Degree Topic-Connected Overlay （MMID-TCO）, is established. This problem is NP-complete and a constant approximation algorithm does not exist for this problem （unless P=NP）. Based on MID metrics, the Maximum Minimum Idle Degree Overlay Design Algorithm （MMID-ODA）, which has polynomial time is introduced. To improve performance, an approach that breaks down the problem into several small-scale problems by exploiting the potential inherent disjoint characteristic in the subscription table is presented. Simulation results show that the proposed algorithm is able to achieve better load balance than MinMax-ODA in a heterogeneous environment.

关键词： optimal problem load balancing heterogeneity topic-based publish/subscribe

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An Authentication Method of Distinguishing Proxy's Secure Accident Responsibility

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Wuhan University Journal of Natural Sciences 2007年第1期12卷 109-112页

作者： ZHU Shuren School of Information Science Guangdong University ofBusiness Studies Guangzhou 510320 Guangdong China

The publish/subscribe （pub/sub） paradigm has asynchronous, loosely-coupled and many-to-many communication properties and is widely used in the application of large-scale distributed computing environment. There is the problem that is mutual trustable between network proxies in terms of pub/sub systems and the problem which is hardly to distinguish accident responsibility while the accident happens in Kerberos based on symmetrical encryption algorithm. A proxy identity authentication algorithm based on RSA encryption is proposed to solve the problem of mutual trust between proxies, and the security of the messages is guaranteed through certificate delegation. The algorithm can distinguish accident responsibility. The feasibility analysis, security analysis and efficiency analysis of the algorithm are carried out.

关键词： publish/subscribe identity authentication kerberos secure accident responsibility

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