Skip to main content

Towards SOA (I)

(Part 1)

Given an opportunity to build a new a set of IT systems from scratch, only the latest techniques, technologies and architectural approaches would be used. In the real world, practically every IT organization is faced with legacy applications, a nice euphemism for the old software that’s running most companies. Anywhere from 5 to 30 years old (or more), it’s running on old (style) infrastructures, operating systems, programming languages, etc.

It incorporates years of business logic development. The capabilities (and failings) are well known and well understood. And you probably can’t afford to replace it.

Not only do IT organizations face this problem, IT vendors face a similar challenge. Even the best known ERP and CRM systems are composites of well known functionality with bits of the new tacked on over time.

In all of these cases, decomposing from the big box application model to a service oriented business function model frequently means completely replacing or rewriting systems. And this is simply not a viable option for most people and companies.

So how to you get from here to there? That will be addressed in part 2.

Popular posts from this blog

Integration Spaghetti™

  I’ve been using the term Integration Spaghetti™ for the past 9 years or so to describe what happens as systems connectivity increases and increases to the point of … unmanageability, indeterminate impact, or just generally a big mess.  A standard line of mine is “moving from spaghetti code to spaghetti connections is not an improvement”. (A standard “point to point connection mess” slide, by enterprise architect Jerry Foster from 2001.) In the past few days I’ve been meeting with a series of IT managers at a large customer and have come up with a revised definition for Integration Spaghetti™ : Integration Spaghetti™ is when the connectivity to/from an application is so complex that everyone is afraid of touching it.  An application with such spaghetti becomes nearly impossible to replace.  Estimates of change impact to the application are frequently wrong by orders of magnitude.  Interruption in the integration functioning are always a major disaster – both in terms of th
Read more

Solving Integration Chaos - Past Approaches

A U.S. Fortune 50's systems interconnect map for 1 division, "core systems only". Integration patterns began changing 15 years ago. Several early attempts were made to solve the increasing problem of the widening need for integration… Enterprise Java Beans (J2EE / EJB's) attempted to make independent callable codelets. Coupling was too tight, the technology too platform specific. Remote Method Invocation (Java / RMI) attempted to make anything independently callable, but again was too platform specific and a very tightly coupled protocol. Similarly on the Microsoft side, DCOM & COM+ attempted to make anything independently and remotely callable. However, as with RMI the approach was extremely platform and vendor specific, and very tightly coupled. MQ created a reliable independent messaging paradigm, but the cost and complexity of operation made it prohibitive for most projects and all but the largest of Enterprise IT shops which could devote a focused technology
Read more

From Spaghetti Code to Spaghetti Connections

Twenty five years ago my boss handed me the primary billing program and described a series of new features needed. The program was about 4 years old and had been worked on by 5 different programmers. It had an original design model, but between all the modifications, bug fixes, patches and quick new features thrown in, the original design pattern was impossible to discern. Any pattern was impossible to discern. It had become, to quote what’s titled the most common architecture pattern of today, ‘a big ball of mud’. After studying the program for several days, I informed my boss the program was untouchable. The effort to make anything more than a minor adjustment carried such a risk, as the impact could only be guessed at, that it was easier and less risky to rewrite it from scratch. If they had considered the future impact, they never would have let a key program degenerate that way. They would have invested the extra effort to maintain it’s design, document it property, and consider
Read more