Friday, August 15, 2008

Understanding Enterprise SOA: Book Review

I was handed this book by one of my programmers. He lent it to me because he knew I was doing some reading on the subject and trying to work out how to bring my software developers up to speed with SOA. I didn't get the impression that he had got terribly much from the book himself. After reading it I can see there is benefit for managers but I think there was not enough technical meat in the book for programmers and analysts.

This book is not technical. It can be read by managers, salesmen or students and I think these were the intended audience. The explanations are easy to understand although I found them long-winded and overly simplistic on many occasions.

The authors attempted to explain procedural code as if it was museum artifact. This made me feel very old. It begs the questions whether the developers brought up on object-oriented development and SOA really need a detailed explanation of the concept of procedural code.

On the positive side this books tackles issues that others do not. It has a good non-technical discussion about security issues and there is a lot of discussion about human issues such as training, reorganization and corporate culture.

Oddly for a book written in 2006 I did not find any mention of Enterprise Service Bus (ESB) although it was clear the author was encouraging looking at off-the-shelf SOA management solutions as well as SOA security and routing software.

Eric Pulier in his preface is unbridled in his enthusiasm for SOA standards:

In a spectacular cycle of enlightened self-interest, every major company in the world has build on top of standards which have ushered a potentially exponential release of value from investments in information technology.
Elsewhere in the book there are sufficient cautions to temper this enthusiasm. In particular the authors advise that much of SOA is still hard work and that there are no industry standard solutions to problems such as transaction processing and security.

There is a long and detailed case study running through the book. The authors do not hold back on the multitude of issues that confront an organization adoption SOA. Parts are realistic and even painful for those of us who have been through implementations of a difficult project or technology.

The book has a good history of technologies and standards. The authors make a good point about standards conforming to the Tipping Point model (see references below). This is when a standard reaches a certain level adoption that it suddenly becomes desirable for the majority of developers.

This is not a strong academic text. There are not many references to other information sources. The definitions are not clearly stated and often over-simplify the concepts. Concepts like Enterprise Architecture, Real-Time Computing and loose coupling are all not accurately defined.

"Loose-Coupling" is described but not adequately explained. The authors give the impression that loose-coupling is only about where you can locate services.

Web services, in contrast are loosely coupled. Once a piece of software has been exposed as a web service it is simple to move it to another computer.
This is an important aspect of coupling but is not the whole story as I have identified on previous postings.

The book focuses on synchronous services rather than asynchronous services. This is unfortunate as other texts such as Thomas Erl or Krafzig, Banke & Slama seem to advocate asynchronous services.

The book addresses the Subject of Enterprise Architecture again loosely defined. At one point the book states
There is no institute providing credentials for enterprise architects.

I'll give the authors the benefit of doubt. Perhaps in 2006 there were not the credentials around but these days there are a number of places to get recognized credentials as an IT Architect. The Microsoft Certified Architect programs spring to mind although I will not vouch for the content of these programs.

The authors see SOA as a method for replacing parts of the Data Warehouse. I was not particularly convinced by this. This was an interesting subject which I had not seen before. I think there is benefit in moving the content of SOA logging to the data warehouse but I was not convinced that SOA radically changes the typical data warehouse ETL process.

This is not a book with detail examples of SOAP and WSDL. It will not explain how to code or build services. You will not find much detail on WS-* here either.

Contracts and Service Level Agreements (SLAs) are described in the book. The authors also introduce the Business Level Agreement (BLA). This is agreement to monitor business conditions such as an inventory pile-up causing $100k per minute of cost.

The book is well illustrated with copious diagrams and notes attached to the diagrams. I found myself skipping past a lot of the diagrams because they did not seem to be explaining anything particularly special.

I congratulate the authors for including detail about setting up training programs in the book and explaining how the resources are brought in to deal with the adoption of SOA. This is missing from many other texts and is an important issue today.

The authors emphasize that SOA is an enterprise approach. Under SOA, IT departments put in place infrastructure to serve the enterprise rather than just serving particular applications.

I would recommend other books before this one for most audiences. The simplistic and at times pedantic prose would make it hard to recommend to an IT professional. Nevertheless there are some well-made observations in this book that you are not likely to find elsewhere.


Understanding Enterprise SOA, Eric Pulier and Hugh Taylor with forward by Paul Gaffney, Manning, 2006

The Tipping Point: How Little Things Can Make a Big Difference (ISBN 0-316-31696-2) is a book by Malcolm Gladwell, first published by Little Brown in 2000.

Sunday, August 3, 2008

Will BPM be the Savior of SOA?

My friendly Software AG representative recently gave me a copy of the "BPM Basics for Dummies". This was an interesting little book pitched at the Executive level. It would not help an IT person to get started with any particular product set but would help them understand what all the fuss was about.

BPM (see note below) has been with us since at least the 1980s. It used to a paper process of writing up the process and then getting a team of programmers to build it, then implementing it on usually a big computer that could handle it and then have the computer operators monitoring it.

In the 1990s Business Process Reengineering (BPR) was an approach which changed an organizational process. It involved process diagrams, IT change and business change.

The excitement with BPM is that some of the leg work involved in actually building systems can be removed if the components of the business process are already established. In this case the components are Web Services enabled through an SOA.

What interests me about this is that some of the concepts behind BPM are a lot easier to explain to the business than SOA. You can get out the Lego blocks and explain the benefits of agility until you are blue in the face but you are still only talking in analogies and expecting the business to take a leap of faith. If you show the business a diagram of one of their business processes and then tell the business the cost of changing that business process then that makes sense in terms the business understands. Of course there is a significant investment in infrastructure, tools and services to establish before you get to that point. It is this significant investment that the IT executive wants to sell. If you are pushing a plan to buy infrastructure, tools and establish services then the plan will make more business sense if the objective is BPM rather than SOA.

I think Software AG understands this and that is why they are giving out "BPM Basics for Dummies" and not "SOA Basics for Dummies". I think the business will get behind BPM before they will embrace SOA. We may see more push for BPM to business executives and SOA may take a back seat. The IT department however knows it needs SOA to get BPM to work. That is just how it meets the business goal of BPM.


BPM stands for Business Process Management, but you would excused for thinking it stood for Business Process Modeling. The "Management" implies that we are doing a lot more than mapping out the processes. The "Management" moves beyond documenting the processes to making them happen and monitoring their effectiveness.

This is not to be confused with BPMN (Business Process Modeling Notation) where the "M" stands for "Modeling". BPMN however can move beyond an aesthetic model to an operational system by converting it to BPEL.


Kiran Garimella, Michael Lees and Bruce Williams, "BPM Basics for Dummies (Software AG Special Edition)", Wiley Publishing Inc. 2008.