This part of ISO/IEC ISP 11188 specifies the common upper layers elements of Α-profiles (see TR 10000-2, 5.5.3). The common elements are specified by reference to OSI connection-mode standards for the ACSE protocol, the presentation layer protocol, and the session layer protocol. A specification defining an Α-profile (see TR 10000-2, 5.5.3) may reference this part of ISO/IEC ISP 11188 as a common basis for the selection of elements of the upper layers protocols (ACSE, presentation and session) that it uses. The use of this part of ISO/IEC ISP 11188 is supplemented by a statement of the specific upper layers requirements of the referencing specification for the use of ACSE, presentation and session protocol standards. The rest of the Α-profile definition, including, for instance, its use of standards for Application Service Elements (ASE, see also figure 1), follows the general rules of TR 10000-1.