My suggestion (and you saw this coming) is: start with the data. This sounds counterintuitive, since SOA is about offering standardized business processes as services, but the concept of data as a service is actually more viable for companies just beginning to think about SOA. What is a service, after all? It's taking a well-defined process, automating it, making it repeatable and authoritative and available to the company at large. But process-based services are usually more complex and multi-faceted, and don't necessarily mandate data (for instance: "reserve a seat for this customer"). They require a different level of consensus. While you wait for your business users to come to consensus on enterprise-level business processes you could be fixing your master data.
A bio-tech client we're working with now has taken the "start with the data" route. "We need to make sure that we have standardized, reconciled master data to apply our processes to when the time comes," the Director of IT Architecture explained. "Data is a great on-ramp to SOA." Our clients are adopting CDI/MDM hub technologies to not only reconcile their master data, but as a viable and practical pretext to slowly introduce SOA. You know you need to fix your master data. Why not kill two birds with one stone and introduce master data as a service to the enterprise?
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This was first published in May 2007