ESA UNCLASSIFIED – For Official Use Metadata in SOIS Service Primitives F. Torelli & P. Skrzypek CCSDS Spring Meeting /4/2013

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 2 ESA UNCLASSIFIED – For Official Use Outline Definitions The problem with metadata Possible solutions Summary The presentation summarises the discussion initiated in the SOIS WG mailing list “Points of concerns on SOIS and EDS” on 4/3/2013

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 3 ESA UNCLASSIFIED – For Official Use Definitions

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 4 ESA UNCLASSIFIED – For Official Use Definitions SOIS services: service primitives specification implementation-independent services mission-independent, i.e. reusable and reconfigurable Application Support services and applications datalink-independent Implementation-specific: a propriety peculiar of the SW implementation of the service (e.g. callback vs. blocking API) Mission/Application-specific: a propriety peculiar of the mission (e.g. type of sensors, orientation of gyros) Datalink/Bus-specific: A propriety peculiar of the bus in use and will be impacted if the bus changes (e.g. RT address vs. SpW logical address) Dev. Device/Manufacturer-specific: a propriety peculiar of a device type or a device component (e.g. data format of health status, access protocol)

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 5 ESA UNCLASSIFIED – For Official Use Result/Failure Metadata RESULT METADATA The Result Metadata parameter shall be used to provide information generated by the DAS provider to the service invoking entity to provide information related to the successful or failed result of a device access operation. NOTE – The parameter can also include other information indicating failure conditions, e.g., that the specified request could not be serviced within the managed timeout period or the DAS is not functioning correctly. DAS, CCSDS M-1, page 3-2 ACQUIRE_FROM_DEVICE.indication (Transaction Identifier, Value, Result Metadata, Timestamp (optional)) COMMAND_DEVICE.indication (Transaction Identifier, Result Metadata) READ.indication (MASAP Address, Destination Address, Transaction ID, Memory ID, Start Memory Address, Size, Priority, Channel, Data, Result Metadata) MEMORY_ACCESS_RESULT.indication (MASAP Address, Destination Address, Transaction ID, Memory ID, Start Memory Address, Size, Result Metadata) PACKET_FAILURE.indication (PSSAP Address, PDSAP Address, Failure Metadata)

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 6 ESA UNCLASSIFIED – For Official Use The problem with metadata

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 7 ESA UNCLASSIFIED – For Official Use The problem with metadata 1/2 The result/failure metadata: carry information about the service itself could carry device/bus/implementation-specific information doesn’t imply its data structure or a data type data structure and data type could be different for different services Other service parameters: carry information relevant only to the service user entities (e.g. Value) have straight forward data type (e.g. Transaction Id)

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 8 ESA UNCLASSIFIED – For Official Use The problem with metadata 2/2 SOIS EDS: implementation-independent mission-independent partially datalink-independent device-specific However… 1.Metadata are not specified in the standards (implementation-specific?) 2.EDS can't be specified without specifying Metadata content 3.EDS to be implementation-independent should use implementation- independent Metadata. SOIS Subnetwork SOIS Subnetwork Service Primitives (API, arguments, configuration parameters) SOIS DAS SOIS DAS Service Primitives (API, arguments, configuration parameters) SOIS DVS SOIS DVS Service Primitives (API, arguments, configuration parameters)

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 9 ESA UNCLASSIFIED – For Official Use Possible solutions

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 10 ESA UNCLASSIFIED – For Official Use Possible solutions Possible implementation-independent result/failure metadata: binaryStatus  OK, not OK qualityStatus:  quality fraction between 0 and 1 ternaryStatus:  OK, warning, severe Mandatory values + optional custom data:  binaryStatus as mandatory  implementation-specific data as optional Result/failure metadata to be represented in the DoT and standardised in the Common DoT.

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 11 ESA UNCLASSIFIED – For Official Use Summary

Metadata in SOIS | F. Torelli & P. Skrzypek | CCSDS Spring Meeting 2013 | 15/4/2013 | Slide 12 ESA UNCLASSIFIED – For Official Use Summary Result/failure metadata are not specified in the SOIS services A minimal set of mandatory values for metadata are necessary to build implementation-independent EDS Dictionary of Terms is the natural place where to define and standardise the mandatory values The mandatory values should be agreed “with urgency”, since they are necessary for the continuation of the work on the EDS

ESA UNCLASSIFIED – For Official Use Metadata in SOIS Service Primitives F. Torelli & P. Skrzypek CCSDS Spring Meeting /4/2013