This document specifies common session layer services and requirements to provide independence between unified diagnostic services (ISO 14229-1) and all transport protocols and network layer services (e.g. ISO 13400-2 DoIP, ISO 15765-2 DoCAN, ISO 10681-2 communication on FlexRay, ISO 14230-2 DoK-Line, and ISO 20794-3 CXPI).

This document specifies a common service primitive interface between OSI layer 5 (session) and layer 4 (transport) via so-called service request/indication/confirmation primitives.