One unique aspect of SOA vs. other architecture styles like Object Orientation , Client/Server or even 3-Tier architecture is that it is built for highly distributed systems. Each and every service is a sub-system in itself it can run on its own machine and be located everywhere in the world . Many times, the service itself needs to be distributed in its own right. One reason to use distributed computing inside the service is computational intensive tasks.

 One of my recent projects was the development of a  biometric platform.  The platform can be used for many usage scenarios. A simple scenario is an access control systems - e.g. authorize entrance into a secure building or area. This is a relatively simple scenario as you usually only have to deal with few thousands of people and as a person requests entry she also declares who she is (e.g. using an RFID card with her ID). In these cases you can go to the database, lookup the appropriate record , run the biometric algorithm or algorithms and verify the person is who she says she is. However the same platform also has to work for other, much more demanding and computing intensive scenarios. For example consider a forensics scenario where you have a fingerprint collected at a crime scene, in this case you don’t know who the person you are looking for is, and you have to run your search on basically all the database which can contain millions of records. Keep in mind that when you match a biometric template[1] you calculate the probability of a match (based on the internal structure of the template) and  that each template weights about a one kilobyte you quickly realize that this can be quite a CPU intensive task.

Sometimes when you develop you SOAs you will have algorithmic tasks or other computational heavy tasks such as the one mentioned above and the question is