This part of ISO/IEC 10026 provides a) a statement (clauses 6 to 11) of the nature of the automaton giving the necessary behaviour of each of the participating entities which are providing the OSI TP Service, covering 1) the actions to be taken on receiving request and response primitives issued by a TP Service user invocation; 2) the actions to be taken on receiving indication and confirm primitives issued by the presentation service-provider; 3) the actions to be taken as a result of certain events within the local system; 4) the actions to be taken as a result of interactions with other ASEs; b) the definition (clause 12) of the abstract syntax required to convey the TP protocol control information; c) the conformance requirements to be met by implementations of this protocol (clause 13). The scope of this part of ISO/IEC 10026 is limited to the interconnection of systems; it does not specify or restrict the implementation of possible interfaces within a computer system.