There are a number of SOA models and frameworks that exist in the market, but we will consider those which are the most referenced ones.
SOA modeling
SOA Reference Model
A reference model is an abstract framework to understand and describe the significant entities and relationships among them for some environments. It is used or referred to for development of consistent standards or specifications supporting the environment of the enterprise.
The OASIS SOA Reference Model (SOA-RM) is an abstract framework that provides the fundamental concept of SOA to understand the entities and relationships between them, and for the development of SOA standards within an organization.
In the dictionary, service is defined as An act or a variety of work done by one for another...
