Check out this article from Computing. It is apparent good advice for SOA implementation but as mentioned in my previous post, something has been forgotten - some enterprises provide software as a web app that is their product and revenue generator. This software could be rendered into services behind the firewall, yet is not about business processes and must be treated differently.

A quote from the article:

Mistake No. 3: Leaving SOA to the techies

When the SOA process is left mostly with the IT side of the organisation, services risk being designed to optimise software performance and reliability, but may not fully reflect the business requirements.

Clarity of business interfaces is essential for cross-application integration or multi-organisation use.

What about an interface that provides a specific website feature and is a service in it’s own right? Such an interface is unlikely to be exposed across organizations because it provides a business specific feature we do not wish to share with others. Further such an interface probably has few business requirements though the underlying service may need to support auditing or customer tracking tools.

A further quote:

Mistake No. 1: Irrational SOA exuberance

Excessive numbers of services ­ those that cannot be readily matched to the business model of the application ­ are a sign of an SOA environment where applications need to be checked as they are completed.

Such environments may feature repositories full of services, volumes of documentation and an impressive collection of new tools and middleware, but what they will not have is agility, incremental software versioning or reuse.

Again let’s consider a service that provides a website feature such as recommendations. How much does it have to match the business model? One might argue that SOA is only concerned with business processes but surely we can model other things as services?

So what exactly is a service, what is SOA and where does REST fit in? I’ll cover that next….

Technorati Tags: architecture, distributed systems, soa

Let’s say you sell pottery. Your core business is about making that pottery, perhaps to order but there’s a whole load of additional work you must do around accounting and the like. Perhaps you also ship your pottery via surface carrier, this introduces further work tracking customer details (watch our for pesky privacy regulations), working with couriers etc.

Almost from the get go these days you’ll automate as much of this drudgery as possible using computers, essentially creating a one person IT department that supports your business processes. Obviously the bigger the business gets the more automation you will require, perhaps developing custom software to support the execution of your business processes (all that drudge you have to do but isn’t core). Your IT department will have to grow accordingly, hiring developers, project managers etc.

This standard tale of the relationship between business and technology plays out in many an enterprise every day. IT and in particular software development is a necessary evil, an undesirable cost to be carefully managed.

However for a certain class of enterprise, software is the product. Maybe it’s a shrink wrap product or a set of services provided to customers via the web. There will still be a need to have an IT department to support the business processes and it might well develop software of it’s own. There’s a fundamental difference between these two types of software because one of them is the business’ money generator. This software must be nurtured and tended to carefully, one can’t just add features, one must care about stability, performance, availability, scalability and so on. Money put into this effort is not a cost it’s an investment. Fundamentally, this software is not enterprise IT as most know it.

This key difference is oft-missed by management, vendors and analysts leading to confusion and unnecessary mistakes. I’ll cover one such mistake (related to SOA) in a follow-up post.

Technorati Tags: business, engineering, software