SOA vs Microservices
Should you happen to be researching "Service-Oriented Architecture" (SOA) on the Internet today, the latest articles you are likely to find will typically be titled: "SOA vs microservices". Complicating the battle somewhat is that you will also find respected industry experts, such as Martin Fowler, stating that some “consider microservices to be one form of SOA, perhaps service orientation done right”.
Martin goes on to declare: “The problem…is that SOA means too many different things and that most of the time we come across something called 'SOA' [there is]…a focus on ESBs (Enterprise Service Buses) used to integrate monolithic applications. This common manifestation of SOA has led some microservice advocates to reject the SOA label entirely”. As such, for the remainder of this article, I will assume the use of ESB middleware as a fundamental characteristic of SOA landscapes, as well as representing the most fundamental distinction there is between SOA and REST.