Welcome!

Weblogic Authors: Yeshim Deniz, Elizabeth White, Michael Meiner, Michael Bushong, Avi Rosenthal

Related Topics: Weblogic

Weblogic: Article

Paths to SOA

High Roads, Low Roads, and Roads Less Traveled

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.

The top-down approach, on the other hand, is one of analysis, deep thought, and patience. Service-orientation is infused into the business process layer so that services can be modeled in alignment with business models. The models themselves may need to be built or further refined in order to fully incorporate service-orientation principles.

Then, of course, there's the middle ground - an approach that tries to balance the requirements of the top-down strategy with the efficiency of the bottom-up approach. Known as the "agile" or "meet-in-the-middle" strategy, this path is somewhat of a roller-coaster ride, and sure to challenge the most seasoned project manager.

This article explores these three approaches to building service-oriented solutions. Before we chart each path, though, let's begin by establishing the common project phases associated with a generic SOA delivery life cycle.

SOA Delivery Life-Cycle Phases
Development projects for service-oriented solutions are, on the surface, much like other custom development projects for distributed applications. Web services are designed, developed, and deployed alongside standard components and the usual supporting cast of front and back-end technologies. Once you dig a bit deeper under the layers of service-orientation, though, you'll find that in order to properly construct and position services as part of a standardized SOA, traditional project cycles require some adjustments.

Looking at Figure 1, you may wonder why the first two-phase names are prefixed with "service-oriented" when the remaining phases have names that begin with just "service." The main reason this distinction is made is because it is during the analysis and design stages that SOA characteristics and service-orientation principles are actually incorporated into the solution being built - so much so, that they warrant unique analysis and design processes that are distinctly "service-oriented." The service phases are primarily concerned with the delivery of services that implement the results of service-oriented analysis and design efforts. Let's now explain each of these life-cycle phases.

Service-Oriented Analysis
It is in this initial stage that we determine the potential scope of our SOA. Service layers are mapped out and individual services are modeled as service candidates that compose a preliminary SOA. (Formal service-oriented analysis and step-by-step service modeling processes are provided as part of Chapters 11 and 12 in Service-Oriented Architecture: Concepts, Technology, and Design.)

Service-Oriented Design
Once we know what it is we want to build, we need to determine how it should be constructed. Service-oriented design is a heavily standards-driven phase that incorporates industry conventions and service-orientation principles into the service design process.

This phase therefore confronts service designers with key decisions that establish the hard logic boundaries encapsulated by services. The service layers designed during this stage can also include the orchestration layer, which results in a formal business process definition. (Four step-by-step design processes are provided within Chapters 13 to 16 in Service-Oriented Architecture: Concepts, Technology, and Design.)

Service Development
Next, of course, is the actual construction phase. Here development platform-specific issues come into play, regardless of service type. Specifically, the choice of programming language and development environment will determine the physical form services and orchestrated business processes take, in accordance with their designs. (SOA support in .NET and J2EE platforms is explored in Chapter 18 of Service-Oriented Architecture: Concepts, Technology, and Design.)

Service Testing
Given their generic nature and potential to be reused and composed in unforeseeable situations, services are required to undergo rigorous testing prior to deployment into a production environment. Below is a sampling of some of the key issues facing service testers.

  • What types of service requestors could potentially access a service?
  • Can all service policy assertions be successfully met?
  • What types of exception conditions could a service be potentially subjected to?
  • How well do service descriptions communicate service semantics?
  • Do revised service descriptions alter or extend previous versions?
  • How easily can the services be composed?
  • How easily can the service descriptions be discovered?
  • Is compliance to WS-I profiles required?
  • What data typing-related issues might arise?
  • Have all possible service activities and service compositions been mapped out?
  • Have all compensation processes been fully tested?
  • What happens if exceptions occur within compensation processes?
  • Do all new services comply with existing design standards?
  • Do new services introduce custom SOAP headers? And, if yes, are all potential requestors (including intermediaries) required to do so, capable of understanding and processing them?
  • Do new services introduce functional or QoS requirements that the current architecture does not support?

More Stories By Thomas Erl

Thomas Erl is a best-selling IT author and founder of Arcitura Education Inc., a global provider of vendor-neutral educational services and certification that encompasses the Cloud Certified Professional (CCP) and SOA Certified Professional (SOACP) programs from CloudSchool.com™ and SOASchool.com® respectively. Thomas has been the world's top-selling service technology author for nearly a decade and is the series editor of the Prentice Hall Service Technology Series from Thomas Erl, as well as the editor of the Service Technology Magazine. With over 175,000 copies in print world-wide, his eight published books have become international bestsellers and have been formally endorsed by senior members of many major IT organizations and academic institutions. To learn more, visit: www.thomaserl.com

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


IoT & Smart Cities Stories
The challenges of aggregating data from consumer-oriented devices, such as wearable technologies and smart thermostats, are fairly well-understood. However, there are a new set of challenges for IoT devices that generate megabytes or gigabytes of data per second. Certainly, the infrastructure will have to change, as those volumes of data will likely overwhelm the available bandwidth for aggregating the data into a central repository. Ochandarena discusses a whole new way to think about your next...
CloudEXPO | DevOpsSUMMIT | DXWorldEXPO are the world's most influential, independent events where Cloud Computing was coined and where technology buyers and vendors meet to experience and discuss the big picture of Digital Transformation and all of the strategies, tactics, and tools they need to realize their goals. Sponsors of DXWorldEXPO | CloudEXPO benefit from unmatched branding, profile building and lead generation opportunities.
All in Mobile is a place where we continually maximize their impact by fostering understanding, empathy, insights, creativity and joy. They believe that a truly useful and desirable mobile app doesn't need the brightest idea or the most advanced technology. A great product begins with understanding people. It's easy to think that customers will love your app, but can you justify it? They make sure your final app is something that users truly want and need. The only way to do this is by ...
Digital Transformation and Disruption, Amazon Style - What You Can Learn. Chris Kocher is a co-founder of Grey Heron, a management and strategic marketing consulting firm. He has 25+ years in both strategic and hands-on operating experience helping executives and investors build revenues and shareholder value. He has consulted with over 130 companies on innovating with new business models, product strategies and monetization. Chris has held management positions at HP and Symantec in addition to ...
DXWorldEXPO LLC announced today that Big Data Federation to Exhibit at the 22nd International CloudEXPO, colocated with DevOpsSUMMIT and DXWorldEXPO, November 12-13, 2018 in New York City. Big Data Federation, Inc. develops and applies artificial intelligence to predict financial and economic events that matter. The company uncovers patterns and precise drivers of performance and outcomes with the aid of machine-learning algorithms, big data, and fundamental analysis. Their products are deployed...
Dynatrace is an application performance management software company with products for the information technology departments and digital business owners of medium and large businesses. Building the Future of Monitoring with Artificial Intelligence. Today we can collect lots and lots of performance data. We build beautiful dashboards and even have fancy query languages to access and transform the data. Still performance data is a secret language only a couple of people understand. The more busine...
Cell networks have the advantage of long-range communications, reaching an estimated 90% of the world. But cell networks such as 2G, 3G and LTE consume lots of power and were designed for connecting people. They are not optimized for low- or battery-powered devices or for IoT applications with infrequently transmitted data. Cell IoT modules that support narrow-band IoT and 4G cell networks will enable cell connectivity, device management, and app enablement for low-power wide-area network IoT. B...
The hierarchical architecture that distributes "compute" within the network specially at the edge can enable new services by harnessing emerging technologies. But Edge-Compute comes at increased cost that needs to be managed and potentially augmented by creative architecture solutions as there will always a catching-up with the capacity demands. Processing power in smartphones has enhanced YoY and there is increasingly spare compute capacity that can be potentially pooled. Uber has successfully ...
SYS-CON Events announced today that CrowdReviews.com has been named “Media Sponsor” of SYS-CON's 22nd International Cloud Expo, which will take place on June 5–7, 2018, at the Javits Center in New York City, NY. CrowdReviews.com is a transparent online platform for determining which products and services are the best based on the opinion of the crowd. The crowd consists of Internet users that have experienced products and services first-hand and have an interest in letting other potential buye...
When talking IoT we often focus on the devices, the sensors, the hardware itself. The new smart appliances, the new smart or self-driving cars (which are amalgamations of many ‘things'). When we are looking at the world of IoT, we should take a step back, look at the big picture. What value are these devices providing. IoT is not about the devices, its about the data consumed and generated. The devices are tools, mechanisms, conduits. This paper discusses the considerations when dealing with the...