If we take back the example that we studied previously, the Abstract Syntax shared by the two applications would have the following specification:

- All the Application Data Values that are exchanged are triplets made of an integer, a boolean and a character string.

- The integer has the range -32768 to +32767

- The character string is exactly 3 characters long, and the characters permitted must be selected from the character register used in the International Alphabet n°5 (IA5, encoded as ASCII, but not necessarily using the 7-bits encoding mentioned in that standard - ).

In the definition of the Abstract Syntax, there shall be no mention concerning the organization of the octets within the representations of the messages (ordering, lengths, etc...). The focus is only on an exhaustive definition of the set of values that can be exchanged between the applications.