If we try to summarize the relationship between the Abstract Syntax and the Transfer Syntax, we conclude that:

- The Abstract Syntax is thus named because it consists in some "abstraction" of the Transfer Syntax (the specification of the representation is omitted).

- The relationship between the Abstract Syntax and the Transfer Syntax is not a one to one relationship ; for a given set of values, there are many ways to attach a set of encoding to these values (different representation techniques) including the arbitrary allocation of representations.

- The usual way, however, consists in applying some systematic rules, which simplifies the implementation of the encoding/decoding. Such systematic rules are called "Encoding Rules". Agreeing on a given couple (Abstract Syntax, Transfer Syntax) can thus be changed into some agreement on a couple (Abstract Syntax, Encoding Rules) because of the equation : Transfer-Syntax = Abstract-Syntax composed with the Encoding-Rules.