Latest News from Thomas Erl

Book Excerpt: Service-Oriented Computing Fundamentals

Mon, 27 Jun 2011 11:45:00 EDT

This excerpt describes fundamental terms and concepts associated with service-oriented computing, including those related to service-oriented architecture, service-orientation, and cloud computing. Service-oriented computing is an umbrella term that represents a new generation distributed computing platform. As such, it encompasses many things, including its own design paradigm and design principles, design pattern catalogs, pattern languages, a distinct architectural model, and related concepts, technologies, and frameworks. Service-orientation (explained shortly) emerged as a formal method in support of achieving the following goals and benefits associated with service-oriented computing.

Cloud Computing, SOA and Windows Azure - Part 4

Thu, 09 Sep 2010 21:30:00 EDT

The following section demonstrates the creation of a simple “Hello World” service in a Windows Azure hosted application. Note: If you are carrying out the upcoming steps with Visual Studio 2008, you will need to be in an elevated mode (such as Administrator). A convenient way of determining whether the mode setting is correct is to press the F5 key in order to enter debug mode. If you receive an error stating “the development fabric must be run elevated,” then you will need to restart Visual Studio as an administrator.

Cloud Computing, SOA and Windows Azure - Part 3

Sat, 28 Aug 2010 10:00:00 EDT

A cloud service in Windows Azure will typically have multiple concurrent instances. Each instance may be running all or a part of the service’s codebase. As a developer, you control the number and type of roles that you want running your service. Windows Azure roles are comparable to standard Visual Studio projects, where each instance represents a separate project. These roles represent different types of applications that are natively supported by Windows Azure.

Cloud Computing, SOA and Windows Azure - Part 2

Fri, 06 Aug 2010 09:00:00 EDT

The Windows Azure platform is an Internet-scale cloud computing services platform hosted in Microsoft data centers. Windows tools provide functionality to build solutions that include a cloud services operating system and a set of developer services. The key parts of the Windows Azure platform are Windows Azure (application container), Microsoft SQL Azure, and Windows Azure platform AppFabric. The infrastructure and service architectures that underlie many of these native services (as well as cloud-based services in general) are based on direct combined application of Stateful Services [786] and Redundant Implementation [766]. This is made possible by leveraging several of the built-in extensions and mechanisms provided by the Windows Azure platform (as explained in this chapter and Chapter 16).

Cloud Computing, SOA and Windows Azure

Sun, 01 Aug 2010 17:45:00 EDT

Microsoft’s Software-plus-Services strategy represents a view of the world where the growing feature-set of devices and the increasing ubiquity of the Web are combined to deliver more compelling solutions. Software-plus-Services represents an evolutionary step that is based on existing best practices in IT and extends the application potential of core service-orientation design principles. The Windows Azure platform represents one of the major components of the Software-plus-Services strategy, as Microsoft’s cloud computing operating environment, designed from the outset to holistically manage pools of computation, storage and networking; all encapsulated by one or more services.

Web Service Contract Design & Versioning for SOA

Thu, 21 May 2009 13:30:00 EDT

It’s always good to get an idea of the big picture before diving into the details of any technology-centric topic. For this reason, we’ll take the time to briefly mention the overarching goals and benefits associated with service-oriented computing as they relate to Web Service contract design.

SOA Pattern of the Week (#5): Service Decomposition

Tue, 07 Apr 2009 08:45:00 EDT

A service inventory is a living body of services that individually will need the freedom to evolve independently over time. What we learned when documenting the SOA design pattern catalog is that there are patterns that emerged not only at design-time but also during this post-implementation evolutionary stage in a service’s lifecycle.

SOA Pattern of the Week (#4): Service Normalization

Fri, 27 Feb 2009 11:30:00 EST

Like data normalization, the Service Normalization pattern is intent on reducing redundancy and waste in order to avoid the governance burden associated with having to maintain and synchronize similar or duplicate bodies of service logic. When designing data architectures, you can easily end up with different databases or even different database tables containing the same or similar data.

SOA Pattern of the Week (#3): Domain Inventory

Mon, 16 Feb 2009 10:30:00 EST

The internationally acclaimed book "SOA Design Patterns" (Erl et al., ISBN: 0136135161, Prentice Hall, 2009) documents a catalog of 85 patterns and is the latest title in the “Prentice Hall Service-Oriented Computing Series from Thomas Erl” (www.soabooks.com). Thomas Erl, the world’s top-selling SOA author, spearheaded the community effort behind the creation of SOA Design Patterns. In development for over three years, the catalog has been subjected to comprehensive reviews by hundreds of industry professionals, employed by many of the world’s leading technology companies. This book was released in coordination with the launch of www.soapatterns.org, a community site dedicated to the on-going development and expansion of the SOA patterns catalog. The "SOA Pattern of the Week" article series is comprised of original content and insights provided to you courtesy of the authors and contributors of the SOA Design Patterns book and the SOAPatterns.org community site. Each article provides a summarized description (600-800 words) of one pattern with some new insights to complement and build upon the content in the book.

SOA Pattern of the Week (#1): Service Façade

Wed, 11 Feb 2009 11:54:00 EST

One of the fundamental goals when designing service-oriented solutions is to attain a reduced degree of coupling between services, thereby increasing the freedom and flexibility with which services can be individually evolved. Achieving the right level of coupling “looseness” is most often considered a design issue that revolves around the service contract and the consumer programs that form dependencies upon it.

SOA Pattern of the Week (#2): Non-Agnostic Context

Wed, 28 Jan 2009 16:20:00 EST

Should a service only be considered a service if it's reusable? The answer to this question, as asserted by this pattern, is a firm "no." While agnostic services (services providing multi-purpose logic with reuse potential, as per the Agnostic Context pattern), receive the most attention during service modeling and design phases, it can often be short-sighted to focus only on agnostic service logic.

Introducing SOA Design Patterns

Sat, 16 Aug 2008 14:15:00 EDT

Originally inspired by techniques used to design buildings and cities, and popularized by the Gang of Four during the mainstream emergence of object-orientation, design patterns have seen us through the various shifts in architecture, technology, and, of course, design. Pattern catalogs have periodically emerged, one building on the other, and each revealing a set of problem-solving techniques and providing invaluable insights as to how and when those techniques should be used to help us attain our design goals.

Exclusive SOA Web Services Journal Briefing – Thomas Erl On SOA

Sat, 29 Oct 2005 06:00:00 EDT

Thomas Erl recently completed a lengthy research project for SOA Systems Inc. into the origins of SOA and the current state of service-orientation among all primary SOA technology platforms. We caught up with him to ask him to share some of the insights he gained from his work with SOA and service-orientation.

Paths to SOA

Mon, 08 Aug 2005 12:00:00 EDT

Many are comparing notes on two well-publicized paths to achieving SOA. The bottom-up approach is currently the most common variety, where Web services are created on an 'as need' basis to fulfill mostly integration-related requirements. These services are typically application specific and simply re-create traditional integration channels over the open Web services communication framework.

A Look Ahead to the Service-Oriented World

Wed, 06 Apr 2005 00:00:00 EDT

BEA recently announced that it is broadening its SOA consulting practice, and that it has created a tool companies can use to learn about SOA and figure out how prepared they are to transition to the new architectural model.

Best Practices for Transition Planning

Thu, 28 Oct 2004 00:00:00 EDT

Despite the magnitude of a migration to a service-oriented platform, the continuing uncertainty of critical WS-* standards, and the often thundering impact of large-scale SOA deployments, now is the time to start considering the move.