This march 2013, I give a “SOA Analysis” workshop at one of my customers.
Using a false scenario and pseudo business process, during the first workshop, we perform SOA Service Identification via the clarification of the architecture using a System Context Diagram. Then we identify the key system capabilities required for enabling the business process. From there, after looking at the messages exchanged between systems and the opportunity to use an Entreprise Data Model for those, we continue towards a Service Candidate List containing : Service Name, Capability Name, Capability Description, Input, Output, Consumer and Provider.
In the second workshop, we take one of the services out of the candiate list and specify it completely : functional context, quality of service, SLA, security, capabilities, pre-post conditions, exceptions… I also stress the importance of UML modeling for SOA by showing examples in Entreprise Architect.
The Service Identification and Modeling phases are part of the generic SOA Governance Lifecycle defined by Thomas Erl.
As main white papers underlying the workshop I recommend the following reading:
– IBM / Arsanjani – “SOMA: A method for developing service-oriented solutions“
– Oracle – SOA RA (Reference Architecture) Foundation v 3.1
– Thomas Erl, Understanding SOA Governance (see free chapter in pdf, includes the Service Lifecycle )