Click here to close now.

Welcome!

SOA & WOA Authors: David Sprott, Jason Bloomberg, AppDynamics Blog, Pat Romanski, Tom Scearce

Related Topics: SOA & WOA

SOA & WOA: Article

Exclusive SOA Web Services Journal Briefing – Thomas Erl On SOA

The Principles of Service-Orientation

With the unwavering prominence of service-oriented architecture (SOA) there is an increasing interest in understanding what exactly it means for something to be considered "service-oriented." 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. This body of work contributed to the mainstream SOA methodology developed by SOA Systems and was also documented in Thomas's new book, Service-Oriented Architecture: Concepts, Technology, and Design. We caught up with Thomas (a previous contributor to WSJ) to ask him to share some of the insights he gained from his work with SOA and service-orientation.

There's no need to mention that SOA has become a major focal point of the IT industry and a primary consideration on numerous corporate agendas. Nor is there a need to get into how SOA has been so heavily promoted that the term has already reached hall-of-fame status as one of the most recognized acronyms in IT history.

What is more important than the term itself is the impact its perceived meaning continues to have on how automation solutions are constructed. Its popularity to date is largely the result of vendors advertising SOA support or capability as part of their product lines. Because SOA has been so vendor-driven, its meaning has been somewhat divergent, skewed by proprietary technology that is still identified with common characteristics that transcend proprietary boundaries.

These common characteristics are critical to defining and understanding an abstract technology architecture classified as "service-oriented." Viewing SOA in abstract is what establishes an agnostic reference point from which proprietary implementations can be measured and, ultimately, unified.

Vendor-Oriented Service-Orientation
Vendors and other organizations in the SOA space have published numerous papers, blueprints, and even frameworks. Most such documents serve the dual purpose of educating readers about SOA while marketing related products or services. This is nothing new. Past variations of client-server and distributed architecture models have varied significantly in both technology and design, depending mostly on who and what was used to implement them.

However, because a core expectation of SOA is its ability to harmonize and streamline diverse technical environments, preserving an abstract viewpoint is required to achieving its potential. This is because SOA, when elevated to an enterprise level, can be used to establish an ecosystem in which an agnostic, overarching framework transcends proprietary environments and constraints.

How the components and elements within this framework are shaped and standardized is of critical importance. This underlines the need for a design paradigm that is sufficiently generic so that it can be applied to solutions regardless of implementation, while remaining in alignment with where powerhouse vendors and organizations are currently taking the technology that is fueling the service-oriented computing platform.

Service-Orientation and Object-Orientation
Design paradigms have played an important role in the evolution of technology and application architecture. The most widely recognized paradigm for distributed business automation has been object-orientation. The system-wide implementation technology for object-oriented solutions has traditionally been proprietary, where, despite the use of the agnostic principles of object-orientation, objects or components are designed to function and interact by using technology and protocols specific to a computing and/or vendor platform.

Service-orientation owes much of its existence to object-orientation. Like traditional multitiered architectures, SOA is based on a model wherein solution logic is distributed. As with object-orientation, concepts such as encapsulation, abstraction, and reusability are fundamental to the design of distributed units of automation logic (services) within SOA. Key differences in these approaches are focused on how these units relate to each other and the scope at which the respective paradigms can be applied.

See Figure 1

Service-Orientation and the Separation of Concerns
I have yet to find a better means of explaining service-orientation than to reach back to that fundamental software engineering theory known as the "separation of concerns." This theory essentially proposes that larger problems be decomposed into a series of individually identifiable problems or "concerns." The logic required to address or solve the larger problem can then also be broken down into individual units of logic that address specific concerns.

Past design paradigms and development platforms have applied this theory in different ways. Component-based and object-oriented designs, for example, provide specific approaches for the decomposition of concerns and the design of corresponding solution logic. Service-orientation establishes a new and distinct means of realizing a separation of concerns. As a design paradigm, it is an evolution of past approaches, augmented and extended in support of the overall goals and characteristics of SOA.

See Figure 2

Common Service-Orientation Principles
Service-orientation began with a modest scope - a basic set of principles centered on an architectural model focused primarily on distinguishing services as reusable and discoverable resources. However, technology architecture in support of service-orientation is making significant strides, and extending its reach into key realms of enterprise computing.

Expectations are being raised surrounding a new era of business automation composed of services as adaptive, shared software assets that promise to infuse an enterprise with organization-level agility, federated interoperability, and vendor independence. These expectations have placed demands on what a distributed automation solution classified as "service-oriented" should be capable of, expanding the breadth of the service-oriented paradigm and adding to and further shaping its principles.

So far, eight common and fundamental principles have been identified. Note that these are classified as "common" in that they represent a cross-section of the most widely accepted design approaches and best practices promoted and practiced by the organizations most responsible for realizing the contemporary SOA movement.

Here then are the common principles of service-orientation:

  • services are loosely coupled
  • services share a formal contract
  • services abstract underlying logic
  • services are composable
  • services are reusable
  • services are autonomous
  • services are stateless
  • services are discoverable

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 (3) View Comments

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.


Most Recent Comments
erl 10/29/05 06:17:48 AM EDT

{{{ have yet to find a better means of explaining service-orientation than to reach back to that fundamental software engineering theory known as the "separation of concerns." }}}

I'd not heard this one before. Useful phrase.

queZZtion 10/29/05 05:36:51 AM EDT

||| technology architecture in support of service-orientation is making significant strides, and extending its reach into key realms of enterprise computing |||

The age of SOA will last much longer than the age of client/server. How long though?

Short&Sweet 10/29/05 05:32:53 AM EDT

Erl's book on this subject, Service-Oriented Architecture: Concepts, Technology, and Design has 792 pages - helpful to have this boiled down to just 3 pages here!

@ThingsExpo Stories
Analytics is the foundation of smart data and now, with the ability to run Hadoop directly on smart storage systems like Cloudian HyperStore, enterprises will gain huge business advantages in terms of scalability, efficiency and cost savings as they move closer to realizing the potential of the Internet of Things. In his session at 16th Cloud Expo, Paul Turner, technology evangelist and CMO at Cloudian, Inc., will discuss the revolutionary notion that the storage world is transitioning from mere Big Data to smart data. He will argue that today’s hybrid cloud storage solutions, with commodity...
Cloud data governance was previously an avoided function when cloud deployments were relatively small. With the rapid adoption in public cloud – both rogue and sanctioned, it’s not uncommon to find regulated data dumped into public cloud and unprotected. This is why enterprises and cloud providers alike need to embrace a cloud data governance function and map policies, processes and technology controls accordingly. In her session at 15th Cloud Expo, Evelyn de Souza, Data Privacy and Compliance Strategy Leader at Cisco Systems, will focus on how to set up a cloud data governance program and s...
Roberto Medrano, Executive Vice President at SOA Software, had reached 30,000 page views on his home page - http://RobertoMedrano.SYS-CON.com/ - on the SYS-CON family of online magazines, which includes Cloud Computing Journal, Internet of Things Journal, Big Data Journal, and SOA World Magazine. He is a recognized executive in the information technology fields of SOA, internet security, governance, and compliance. He has extensive experience with both start-ups and large companies, having been involved at the beginning of four IT industries: EDA, Open Systems, Computer Security and now SOA.
Every innovation or invention was originally a daydream. You like to imagine a “what-if” scenario. And with all the attention being paid to the so-called Internet of Things (IoT) you don’t have to stretch the imagination too much to see how this may impact commercial and homeowners insurance. We’re beyond the point of accepting this as a leap of faith. The groundwork is laid. Now it’s just a matter of time. We can thank the inventors of smart thermostats for developing a practical business application that everyone can relate to. Gone are the salad days of smart home apps, the early chalkb...
The industrial software market has treated data with the mentality of “collect everything now, worry about how to use it later.” We now find ourselves buried in data, with the pervasive connectivity of the (Industrial) Internet of Things only piling on more numbers. There’s too much data and not enough information. In his session at @ThingsExpo, Bob Gates, Global Marketing Director, GE’s Intelligent Platforms business, to discuss how realizing the power of IoT, software developers are now focused on understanding how industrial data can create intelligence for industrial operations. Imagine ...
We certainly live in interesting technological times. And no more interesting than the current competing IoT standards for connectivity. Various standards bodies, approaches, and ecosystems are vying for mindshare and positioning for a competitive edge. It is clear that when the dust settles, we will have new protocols, evolved protocols, that will change the way we interact with devices and infrastructure. We will also have evolved web protocols, like HTTP/2, that will be changing the very core of our infrastructures. At the same time, we have old approaches made new again like micro-services...
Operational Hadoop and the Lambda Architecture for Streaming Data Apache Hadoop is emerging as a distributed platform for handling large and fast incoming streams of data. Predictive maintenance, supply chain optimization, and Internet-of-Things analysis are examples where Hadoop provides the scalable storage, processing, and analytics platform to gain meaningful insights from granular data that is typically only valuable from a large-scale, aggregate view. One architecture useful for capturing and analyzing streaming data is the Lambda Architecture, representing a model of how to analyze rea...
SYS-CON Events announced today that Vitria Technology, Inc. will exhibit at SYS-CON’s @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Vitria will showcase the company’s new IoT Analytics Platform through live demonstrations at booth #330. Vitria’s IoT Analytics Platform, fully integrated and powered by an operational intelligence engine, enables customers to rapidly build and operationalize advanced analytics to deliver timely business outcomes for use cases across the industrial, enterprise, and consumer segments.
Today’s enterprise is being driven by disruptive competitive and human capital requirements to provide enterprise application access through not only desktops, but also mobile devices. To retrofit existing programs across all these devices using traditional programming methods is very costly and time consuming – often prohibitively so. In his session at @ThingsExpo, Jesse Shiah, CEO, President, and Co-Founder of AgilePoint Inc., discussed how you can create applications that run on all mobile devices as well as laptops and desktops using a visual drag-and-drop application – and eForms-buildi...
Docker is an excellent platform for organizations interested in running microservices. It offers portability and consistency between development and production environments, quick provisioning times, and a simple way to isolate services. In his session at DevOps Summit at 16th Cloud Expo, Shannon Williams, co-founder of Rancher Labs, will walk through these and other benefits of using Docker to run microservices, and provide an overview of RancherOS, a minimalist distribution of Linux designed expressly to run Docker. He will also discuss Rancher, an orchestration and service discovery platf...
Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities. Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch of Docker's initial release in March of 2013, interest was revved up several notches. Then late last...
SYS-CON Events announced today that Dyn, the worldwide leader in Internet Performance, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Dyn is a cloud-based Internet Performance company. Dyn helps companies monitor, control, and optimize online infrastructure for an exceptional end-user experience. Through a world-class network and unrivaled, objective intelligence into Internet conditions, Dyn ensures traffic gets delivered faster, safer, and more reliably than ever.
CommVault has announced that top industry technology visionaries have joined its leadership team. The addition of leaders from companies such as Oracle, SAP, Microsoft, Cisco, PwC and EMC signals the continuation of CommVault Next, the company's business transformation for sales, go-to-market strategies, pricing and packaging and technology innovation. The company also announced that it had realigned its structure to create business units to more directly match how customers evaluate, deploy, operate, and purchase technology.
In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect at GE, and Ibrahim Gokcen, who leads GE's advanced IoT analytics, focused on the Internet of Things / Industrial Internet and how to make it operational for business end-users. Learn about the challenges posed by machine and sensor data and how to marry it with enterprise data. They also discussed the tips and tricks to provide the Industrial Internet as an end-user consumable service using Big Data Analytics and Industrial Cloud.
The explosion of connected devices / sensors is creating an ever-expanding set of new and valuable data. In parallel the emerging capability of Big Data technologies to store, access, analyze, and react to this data is producing changes in business models under the umbrella of the Internet of Things (IoT). In particular within the Insurance industry, IoT appears positioned to enable deep changes by altering relationships between insurers, distributors, and the insured. In his session at @ThingsExpo, Michael Sick, a Senior Manager and Big Data Architect within Ernst and Young's Financial Servi...
Performance is the intersection of power, agility, control, and choice. If you value performance, and more specifically consistent performance, you need to look beyond simple virtualized compute. Many factors need to be considered to create a truly performant environment. In his General Session at 15th Cloud Expo, Harold Hannon, Sr. Software Architect at SoftLayer, discussed how to take advantage of a multitude of compute options and platform features to make cloud the cornerstone of your online presence.
Even as cloud and managed services grow increasingly central to business strategy and performance, challenges remain. The biggest sticking point for companies seeking to capitalize on the cloud is data security. Keeping data safe is an issue in any computing environment, and it has been a focus since the earliest days of the cloud revolution. Understandably so: a lot can go wrong when you allow valuable information to live outside the firewall. Recent revelations about government snooping, along with a steady stream of well-publicized data breaches, only add to the uncertainty
The explosion of connected devices / sensors is creating an ever-expanding set of new and valuable data. In parallel the emerging capability of Big Data technologies to store, access, analyze, and react to this data is producing changes in business models under the umbrella of the Internet of Things (IoT). In particular within the Insurance industry, IoT appears positioned to enable deep changes by altering relationships between insurers, distributors, and the insured. In his session at @ThingsExpo, Michael Sick, a Senior Manager and Big Data Architect within Ernst and Young's Financial Servi...
PubNub on Monday has announced that it is partnering with IBM to bring its sophisticated real-time data streaming and messaging capabilities to Bluemix, IBM’s cloud development platform. “Today’s app and connected devices require an always-on connection, but building a secure, scalable solution from the ground up is time consuming, resource intensive, and error-prone,” said Todd Greene, CEO of PubNub. “PubNub enables web, mobile and IoT developers building apps on IBM Bluemix to quickly add scalable realtime functionality with minimal effort and cost.”
The Internet of Things (IoT) is rapidly in the process of breaking from its heretofore relatively obscure enterprise applications (such as plant floor control and supply chain management) and going mainstream into the consumer space. More and more creative folks are interconnecting everyday products such as household items, mobile devices, appliances and cars, and unleashing new and imaginative scenarios. We are seeing a lot of excitement around applications in home automation, personal fitness, and in-car entertainment and this excitement will bleed into other areas. On the commercial side, m...