machine; ROSE=remote operations service element The structure shows that an AF must be made part of an OSI application layer element that includes a CMISE, an ACSE, and a ROSE, and possibly also an FTAM element (for bulk data transfer). The actual structure defined by the layer interfaces in the application layer element is the author's best guess, since the standards are somewhat vague in this respect. The structure indicates that an AF must use the other service elements in a particular order, since they all operate over the same "presentation connection." Every element in the structure, except the AF, is specified as a layer, i.e., by a "service definition" and a protocol specification (the AF falls outside what the OSI RM defines). Since actually neither of the elements are real layer elements in the sense that they create and interpret messages (messages are first created by the presentation layer), and therefore define no LPM, a large set of complicated speci- fications and artificial state machines have been produced that exist only because the OSI RM upper layer architecture says SO. According to our discussion in Sect. 6.2, CMIS, ROSE, and ACSE are all functions of an agent layer and therefore belong to the same LPM. AFs and OSF are actors of such agents and define an LSM that is supported by that LPM. This becomes particular obvious by the protocol specification CMIP: as can be expected, the only thing the CMISE has to do is to map primitives of CMIS opera- tions on primitives of ROSE operations (i.e., act as a translator between two levels of meta-primitives). We can therefore expect "CMIP messages" to be identical to CMISE primitives which will be mapped one-to-one on ROSE-primitives, which is 5 Management and Traffic Systems exactly what happens in the CMISE (although CMISE renames its "messages," presumably in order to make the effort of specifying the protocol worthwhile). Thus, we can conclude that the OSI upper layer architecture was forced on network designers as a (doubtful) specification metho