ISO 22666:2016

Overview - What ISO 22666:2016 covers

ISO 22666:2016 - Space data and information transfer systems - AOS (Advanced Orbiting Systems) Space Data Link Protocol - defines the AOS space data link protocol at the service, protocol-data-unit (PDU), and procedural level. Prepared by CCSDS and adopted by ISO, this third edition (2016) standard specifies the services offered to users, the types of protocol data units used, and the procedures performed by the protocol entity. It does not prescribe specific implementations, hardware products, low-level technologies, or operational management practices.

Keywords: ISO 22666:2016, AOS Space Data Link Protocol, space data link, CCSDS, AOS transfer frame, virtual channel

Key technical topics and requirements

The standard documents the architecture and behavior of the AOS data link including:

• Service definitions
  • Virtual Channel Packet (VCP) service, Bitstream (B) service, Virtual Channel Access (VCA) service, and others.
• Protocol Data Units (PDUs)
  • AOS transfer frames and multiplexing/bitstream PDUs (e.g., M_PDU, B_PDU).
• Frame and field structures
  • AOS transfer frame primary header, Virtual Channel Frame (VCF), Master Channel Frame (MCF) organization.
• Procedures
  • Sending-end and receiving-end protocol procedures for packet/bitstream handling, virtual channel generation and reception, and insertion services.
• Operational controls and managed parameters
  • Virtual channel operational control fields (VC_OCF), managed parameters for physical/master/virtual channels and packet transfer.
• Options and updates
  • Support for the Space Data Link Security (SDLS) option, frame error control field encoding updates, and rules for idle packet/OID frames.

The standard also provides abstract models, logic diagrams, and describes assumed lower-layer services (relationship with OSI layers).

Keywords: virtual channel, AOS transfer frame, SDLS, protocol data units, frame error control

Practical applications - Who uses ISO 22666:2016

ISO 22666:2016 is used by organizations involved in space mission communications and data systems, including:

• Space agencies (e.g., NASA, ESA, JAXA) for cross-support and interoperability
• Satellite and spacecraft subsystem engineers (telemetry, telecommand, onboard data handling)
• Ground station and mission operations teams for uplink/downlink data link implementations
• Spacecraft software developers and mission integrators implementing data-link services
• Standards bodies and system architects designing interoperable multi-agency missions

Typical applications include satellite telemetry transfer, onboard virtual channel multiplexing, secure space data links (when using SDLS), and multi-mission ground support interoperability.

Keywords: satellite telemetry, ground station, onboard data handling, interoperability

Related standards

• CCSDS recommendations and other ISO/CCSDS standards on space data systems and space data link security (see CCSDS website for current references).