SOA represents a set of agreements among service requesters and service providers that specify what one can / should expect [QoS - quality of service, business & IT metrics].
By Definition
Services agreements are between entities, namely services providers and consumers. These
agreements are based on services specification and not implementation.
Focus is to ensure that the service specification is separate from the implementation, and, each service addresses some / many business requirement(s).
The question to be asked is, "How does one define and enforce service-level agreements so that service functionality can be predictably and contractually delivered to specific service requesters?”
