The figures below show a PUS telecommand and telemetry packet and their utilization within the CCSDS space packet specification. The PUS specification uses the user-definable fields of the CCSDS space packet in order to create a PUS packet. The specification defines a secondary header that provides additional metadata such as the destination application identifier and the packet service type and service subtype. This header will be referred to as the PUS header. These additional fields provide the necessary framework for routing and tracking packets between applications within a JAS-based payload.
"GROUND SYSTEMS AND OPERATIONS - TELEMETRY AND TELECOMMAND PACKAGE UTILIZATION". ECSS-70-41A, European Cooperation for Space Standardization (ECSS), The Netherlands, 2003, GROUND SYSTEMS AND OPERATIONS - TELEMETRY AND TELECOMMAND PACKAGE UTILIZATION.