XML Protocol Abstract Model

This document describes an Abstract Model of XML Protocol. The challenge of crafting a protocol specification is to create a description of behaviour that is not tied to any particular approach to implementation. There is a need to abstract away from some of the messy implementation details of buffer management, data representation and specific APIs. However, in order to describe the behaviour of a protocol one has to establish a set of (useful) concepts that can be used in that description. An abstract model is one way to establish a consistent set of concepts. An abstract model is a tool for the description of complex behaviour — it is not a template for an implementation... although it should not stray so far away from reality that it is impossible to recognise how the required behaviours would be implemented.