Well adapted to the loosely coupled nature of distributed interaction in large-scale applications, the publish/subscribe communication paradigm has recently received increasing attention. With systems based on the publish/subscribe interaction scheme, subscribers register their interest in an event, or a pattern of events, and are subsequently asynchronously notified of events generated by publishers. Many variants of the paradigm have recently been proposed, each variant being specifically adapted to some given application or network model. This paper factors out the common denominator underlying these variants: full decoupling of the communicating entities in time, space, and synchronization. We use these three decoupling dimensions to better identify commonalities and divergences with traditional interaction paradigms. The many variations on the theme of publish/subscribe are classified and synthesized. In particular, their respective benefits and shortcomings are discussed both in terms of interfaces and implementations.

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The many faces of publish/subscribe

http://emamispnu.persiangig.com/Projects/Cloud%20Computing/science_2.pdf

Review: A survey on security issues in service delivery models of cloud computing

Service-oriented architectures (SOA) is an emerging approach that addresses the requirements of loosely coupled, standards-based, and protocol- independent distributed computing. Typically business operations running in an SOA comprise a number of invocations of these different components, often in an event-driven or asynchronous fashion that reflects the underlying business process needs. To build an SOA a highly distributable communications and integration backbone is required. This functionality is provided by the Enterprise Service Bus (ESB) that is an integration platform that utilizes Web services standards to support a wide variety of communications patterns over multiple transport protocols and deliver value-added capabilities for SOA applications. This paper reviews technologies and approaches that unify the principles and concepts of SOA with those of event-based programing. The paper also focuses on the ESB and describes a range of functions that are designed to offer a manageable, standards-based SOA backbone that extends middleware functionality throughout by connecting heterogeneous components and systems and offers integration services. Finally, the paper proposes an approach to extend the conventional SOA to cater for essential ESB requirements that include capabilities such as service orchestration, "intelligent" routing, provisioning, integrity and security of message as well as service management. The layers in this extended SOA, in short xSOA, are used to classify research issues and current research activities.

/pdf/service-oriented-architectures-approaches-technologies-and-1m0bcwz0fm.pdf

Service oriented architectures: approaches, technologies and research issues

Over the Internet today, computing and communications environments are significantly more complex and chaotic than classical distributed systems, lacking any centralized organization or hierarchical control. There has been much interest in emerging Peer-to-Peer (P2P) network overlays because they provide a good substrate for creating large-scale data sharing, content distribution, and application-level multicast applications. These P2P overlay networks attempt to provide a long list of features, such as: selection of nearby peers, redundant storage, efficient search/location of data items, data permanence or guarantees, hierarchical naming, trust and authentication, and anonymity. P2P networks potentially offer an efficient routing architecture that is self-organizing, massively scalable, and robust in the wide-area, combining fault tolerance, load balancing, and explicit notion of locality. In this article we present a survey and comparison of various Structured and Unstructured P2P overlay networks. We categorize the various schemes into these two groups in the design spectrum, and discuss the application-level network performance of each group.

/pdf/a-survey-and-comparison-of-peer-to-peer-overlay-network-cpcv2ij1hk.pdf

A survey and comparison of peer-to-peer overlay network schemes

The components of a loosely coupled system are typically designed to operate by generating and responding to asynchronous events. An event notification service is an application-independent infrastructure that supports the construction of event-based systems, whereby generators of events publish event notifications to the infrastructure and consumers of events subscribe with the infrastructure to receive relevant notifications. The two primary services that should be provided to components by the infrastructure are notification selection (i. e., determining which notifications match which subscriptions) and notification delivery (i.e., routing matching notifications from publishers to subscribers). Numerous event notification services have been developed for local-area networks, generally based on a centralized server to select and deliver event notifications. Therefore, they suffer from an inherent inability to scale to wide-area networks, such as the Internet, where the number and physical distribution of the service's clients can quickly overwhelm a centralized solution. The critical challenge in the setting of a wide-area network is to maximize the expressiveness in the selection mechanism without sacrificing scalability in the delivery mechanism. This paper presents SIENA, an event notification service that we have designed and implemented to exhibit both expressiveness and scalability. We describe the service's interface to applications, the algorithms used by networks of servers to select and deliver event notifications, and the strategies used to optimize performance. We also present results of simulation studies that examine the scalability and performance of the service.

Design and evaluation of a wide-area event notification service

From the Publisher:
This book is a thorough introduction to Java Message Service (JMS), the standard Java application program interface (API) from Sun Microsystems that supports the formal communication known as "messaging" between computers in a network. JMS provides a common interface to standard messaging protocols and to special messaging services in support of Java programs. The messages exchange crucial data between computers, rather than between usersinformation such as event notification and service requests. Messaging is often used to coordinate programs in dissimilar systems or written in different programming languages. 
Using the JMS interface, a programmer can invoke the messaging services of IBM's MQSeries, Progress Software's SonicMQ, and other popular messaging product vendors. In addition, JMS supports messages that contain serialized Java objects and messages that contain Extensible Markup Language (XML) pages. 
Messaging is a powerful new paradigm that makes it easier to uncouple different parts of an enterprise application. Messaging clients work by sending messages to a message server, which is responsible for delivering the messages to their destination. Message delivery is asynchronous, meaning that the client can continue working without waiting for the message to be delivered. The contents of the message can be anything from a simple text string to a serialized Java object or an XML document. 
Java Message Service shows how to build applications using the point-to-point and publish-and-subscribe models; how to use features like transactions and durable subscriptions to make an application reliable; and how to use messaging within Enterprise JavaBeans. It also introduces a new EJB type, the MessageDrivenBean, that is part of EJB 2.0, and discusses integration of messaging into J2EE. 

About the Authors:
Richard Monson-Haefel is a leading expert in Enterprise Java development. He is the architect of OpenEJB, an open source EJB server, and has consulted as an architect on Enterprise JavaBeans, CORBA, Java RMI, and other distributed computing projects over the past several years. Richard is also the author of O'Reilly's Enterprise JavaBeans. 
Dave Chappell is vice president and SonicMQ chief technology evangelist at Progress Software Corp. Dave has over 18 years of industry experience building software tools and infrastructure for application developers, spanning all aspects of R&D, sales, marketing, and support services. Dave has also been published in Network World magazine and has presented technical topics at numerous speaking engagements including JavaOne and XMLOne. 
As director of engineering for SonicMQ, Progress Software's award winning JMS Internet Commerce Messaging System, Dave oversaw the design and development of the fastest and most scalable, reliable, and robust implementation of JMS in the marketplace. 
Dave has under his belt a broad cross-platform background in designing and developing Internet based middleware and distributed object systems across a wide range of technologies including C++, Java, DCOM, CORBA, and EJB. Dave's experience also includes development of client/server infrastructure, graphical user interfaces, language interpreters, and various utility libraries.

Java Message Service

Foreword Preface Part I. The EJB 3.0 Standard 1. Introduction Server-Side Components Persistence and Entity Beans Asynchronous Messaging Web Services Titan Cruises: An Imaginary Business What's Next? 2. Architectural Overview The Entity Bean The Enterprise Bean Component Using Enterprise and Entity Beans The Bean-Container Contract Summary 3. Resource Management and Primary Services Resource Management Primary Services What's Next? 4. Developing Your First Beans Developing an Entity Bean Developing a Session Bean5. Persistence: EntityManager Entities Are POJOs Managed Versus Unmanaged Entities Packaging a Persistence Unit Obtaining an EntityManager Interacting with an EntityManager Resource Local Transactions 6. Mapping Persistent Objects The Programming Model Basic Relational Mapping Primary Keys Property Mappings Multitable Mappings with @SecondaryTable @Embedded Objects 7. Entity Relationships The Seven Relationship Types Mapping Collection-Based Relationships Detached Entities and FetchType Cascading 8. Entity Inheritance Single Table per Class Hierarchy Table per Concrete Class Table per Subclass Mixing Strategies Nonentity Base Classes 9. Queries and EJB QL Query API EJB QL Native Queries Named Queries 10. Entity Callbacks and Listeners Callback Events Callbacks on Entity Classes Entity Listeners11. Session Beans The Stateless Session Bean SessionContext The Life Cycle of a Stateless Session Bean The Stateful Session Bean The Life Cycle of a Stateful Session Bean Stateful Session Beans and Extended Persistence Contexts Nested Stateful Session Beans 12. Message-Driven Beans JMS and Message-Driven Beans JMS-Based Message-Driven Beans The Life Cycle of a Message-Driven Bean Connector-Based Message-Driven Beans Message Linking 13. Timer Service Titan's Maintenance Timer Timer Service API Transactions Stateless Session Bean Timers Message-Driven Bean Timers Final Words 14. The JNDI ENC and Injection The JNDI ENC Reference and Injection Types 15. Interceptors Intercepting Methods Interceptors and Injection Intercepting Life Cycle Events Exception Handling Interceptor Life Cycle Bean Class @AroundInvoke Methods Future Interceptor Improvements 16. Transactions ACID Transactions Declarative Transaction Management Isolation and Database Locking Nontransactional EJBs Explicit Transaction Management Exceptions and Transactions Transactional Stateful Session Beans Conversational Persistence Contexts 17. Security Authentication and Identity Authorization The RunAs Security Identity Programmatic Security 18. EJB 3.0: Web Services Standards Web Services Overview XML Schema and XML Namespaces SOAP 1.1 WSDL 1.1 UDDI 2.0 From Standards to Implementation 19. EJB 3.0 and Web Services Accessing Web Services with JAX-RPC Defining a Web Service with JAX-RPC Using JAX-WS Other Annotations and APIs 20. Java EE Servlets JavaServer Pages Web Components and EJB Filling in the Gaps Fitting the Pieces Together 21. EJB Design in the Real World Predesign: Containers and Databases Design Should You Use EJBs? Wrapping Up Part II. The JBoss Workbook Introduction 1. JBoss Installation and Configuration About JBoss Installing the JBoss Application Server A Quick Look at JBoss Internals Exercise Code Setup and Configuration 2. Exercises for Chapter 4 Exercise 4.1: Your First Beans with JBoss Exercise 4.2: JNDI Binding with Annotations Exercise 4.3: JNDI Binding with XML 3. Exercises for Chapter 5 Exercise 5.1: Interacting with EntityManager Exercise 5.2: Standalone Persistence 4. Exercises for Chapter 6 Exercise 6.1: Basic Property Mappings Exercise 6.2: @IdClass Exercise 6.3: @EmbeddedId Exercise 6.4: Multitable Mappings Exercise 6.5: Embeddable Classes 5. Exercises for Chapter 7 Exercise 7.1: Cascading Exercise 7.2: Inverse Relationships Exercise 7.3: Lazy Initialization 6. Exercises for Chapter 8 Exercise 8.1: Single Table per Hierarchy Exercise 8.2: Single Table per Hierarchy Exercise 8.3: JOINED Inheritance Strategy 7. Exercises for Chapter 9 Exercise 9.1: Query and EJB QL Basics Exercise 9.2: Native SQL Queries 8. Exercises for Chapter 10 Exercise 10.1: Entity Callbacks Exercise 10.2: Entity Listeners 9. Exercises for Chapter 11 Exercise 11.1: Stateless Session Bean Exercise 11.2: XML Override Exercise 11.3: Annotationless tateless Session Bean Exercise 11.4: Stateful Session Bean Exercise 11.5: Annotationless Stateful Session Bean 10. Exercises for Chapter 12 Exercise 12.1: The Message-Driven Bean 11. Exercises for Chapter 13 Exercise 13.1: EJB Timer Service 12. Exercises for Chapter 15 Exercise 15.1: EJB Interceptors Exercise 15.2: Intercepting EJB Callbacks 13. Exercises for Chapter 16 Exercise 16.1: Conversational Persistence Contexts 14. Exercises for Chapter 17 Exercise 17.1: Security Exercise 17.2: Securing Through XML 15. Exercises for Chapter 19 Exercise 19.1: Exposing a Stateless Bean Exercise 19.2: Using a .NET Client Part III. Appendix Appendix:. JBoss Database Configuration Index

Enterprise JavaBeans 3.0

"J2EE(TM) Web Services is written in the tradition of the great books people have come to expect from author Richard Monson-Haefel More than a complete and concise Web services reference, this essential guide is the way for J2EE developers to quickly master Web services architecture and development" -Floyd Marinescu, Author, EJB Design Patterns; Director, TheServerSidecomWeb services are revolutionizing the way enterprises conduct business, as they allow disparate applications to communicate and exchange business data Now, Java 2, Enterprise Edition (J2EE(TM)) delivers a complete Web services platform But how do you make sense of the sea of acronyms in this emerging area? Richard Monson-Haefel comes to the rescue with this essential guide for Java developers who need to understand J2EE APIs for Web services and the Web services standardsJ2EE(TM) Web Services is a comprehensive guide to developing and deploying Web services using J2EE technology Concentrating on standards sanctioned by the Web Services Interoperability Organization (WS-I) for maximum interoperability, the author delves into Web-service standards and the J2EE 14 Web-service APIs and components with clear and engaging discussionsKey topics covered include: XML (eXtensible Markup Language) and XML Schema SOAP (Simple Object Access Protocol) WSDL (Web Services Description Language) UDDI (Universal Description, Discovery, and Integration) JAX-RPC (Java API for XML-based RPC) SAAJ (SOAP with Attachments API for Java) JAXR (Java API for XML Registries) JAXP (Java API for XML Processing)The appendices complement this wealth of information with coverage of XML regular expressions, Base 64 encoding, DTDs (document type definitions), SOAP Messages with Attachments (SwA), RCP/Encoded SOAP messaging, and references to other resources In short, this accessible reference will give Java developers the tools they need to use J2EE technologies and APIs to integrate both enterprise applications and Web-based applications

J2EE Web Services

If you're up on the latest Java technologies, then you know that Enterprise JavaBeans (EJB) 3.0 is the hottest news in Java this year. In fact, EJB 3.0 is being hailed as the new standard of server-side business logic programming. And O'Reilly's award-winning book on EJB has been refreshed just in time to capitalize on the technology's latest rise in popularity.This fifth edition, written by Bill Burke and Richard Monson-Haefel, has been updated to capture the very latest need-to-know Java technologies in the same award-winning fashion that drove the success of the previous four strong-selling editions. Bill Burke, Chief Architect at JBoss, Inc., represents the company on the EJB 3.0 and Java EE 5 specification committees. Richard Monson-Haefel is one of the world's leading experts on Enterprise Java.Enterprise JavaBeans 3.0, 5th Edition is organized into two parts: the technical manuscript followed by the JBoss workbook. The technical manuscript explains what EJB is, how it works, and when to use it. The JBoss workbook provides step-by-step instructions for installing, configuring, and running the examples from the manuscript on the JBoss 4.0 Application Server.Although EJB makes application development much simpler, it's still a complex and ambitious technology that requires a great deal of time to study and master. But now, thanks to Enterprise JavaBeans 3.0, 5th Edition, you can overcome the complexities of EJBs and learn from hundreds of practical examples that are large enough to test key concepts but small enough to be taken apart and explained in the detail that you need. Now you can harness the complexity of EJB with just a single resource by your side.

Enterprise JavaBeans 3.0 (5th Edition)

A computerized system and method are presented that creates implicit content on a mobile device by monitoring and recording input from sensors on the device. Metadata from the implicit content and from user-created content is then analyzed for the purpose of event identification. Using the metadata and event identification, the content is created into clusters, which can be confirmed by the user as actual events. Events can then be grouped according to metadata and event information into a presentation grouping. Users can also be associated with organizations, allowing the sharing of content and event definitions between the organization and its member users. Users can create ad hoc organizations with a particular subset of other users, which simplifies the creation of event meta data and content sharing with other users in the ad hoc organization.

Richard Monson-Haefel

Papers

Java Message Service

Enterprise JavaBeans 3.0

J2EE Web Services

Enterprise JavaBeans 3.0 (5th Edition)

Group membership content presentation and augmentation system and method