The Network Communication Services specified in PS3.8 are a set of generic services provided to support the communication of DICOM Application Entities. They are a proper subset of the services offered by the OSI Presentation Service (ISO 8822) and of the OSI Association Control Service Element (ACSE) (ISO 8649). They shall be referred to as the Upper Layer Service or UL Service. The DICOM UL Service is specified in Section 7.

This UL Service is provided by the Upper Layer Protocol for TCP/IP (see Section 9).

Figure 6-1 shows the TCP/IP protocol stack that is available to support the communication of DICOM Application Entities.