Indication primitive shall be the service indication

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Unformatted text preview: 2003 CCSDS RECOMMENDATION FOR TM SPACE DATA LINK PROTOCOL 3.5.3.3.2 Semantics The VC_FSH.indication primitive shall provide parameters as follows: VC_FSH.indication 3.5.3.3.3 (FSH_SDU, GVCID, FSH_SDU Loss Flag (optional)) When Generated The VC_FSH.indication primitive shall be passed from the service provider to the VC_FSH Service user at the receiving end to deliver an FSH_SDU. 3.5.3.3.4 Effect On Receipt The effect of receipt of the VC_FSH.indication primitive by the VC_FSH Service user is undefined. 3.5.3.3.5 Additional Comments The VC_FSH.indication primitive shall be used to deliver FSH_SDUs to the VC_FSH Service user identified by the GVCID. 3.6 VIRTUAL CHANNEL OPERATIONAL CONTROL FIELD (VC_OCF) SERVICE 3.6.1 OVERVIEW OF VC_OCF SERVICE The Virtual Channel Operational Control Field (VC_OCF) Service provides synchronous transfer of fixed-length data units, each consisting of four octets, in the Operational Control Field (OCF) of Transfer Frames of a Virtual Channel. The service is unidirectional and sequence-preserving. The transfer is synchronized with the release of Transfer Frames of a Virtual Channel. The service does not guarantee completeness, but it may signal gaps in the sequence of service data units delivered to the receiving user. Only one user, identified with the GVCID of the Virtual Channel, can use this service on a Virtual Channel. Service data units from different users are not multiplexed together within one Virtual Channel. CCSDS 132.0-B-1 Page 3-12 September 2003 CCSDS RECOMMENDATION FOR TM SPACE DATA LINK PROTOCOL 3.6.2 VC_OCF SERVICE PARAMETERS 3.6.2.1 General The parameters used by the VC_OCF Service primitives shall conform to the specifications contained in 3.6.2.2 through 3.6.2.4. 3.6.2.2 OCF_SDU NOTE – The OCF_SDU parameter is the service data unit transferred by the VC_OCF Service in the Operational Control Field of Transfer Frames of a Virtual Channel. For restrictions on the OCF_SDU transferred by the VC_OCF Service, see 3.2.5. 3.6.2.3 GVCID The GVCID parameter shall contain a GVCID that indi...
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This document was uploaded on 03/06/2014.

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