Unformatted text preview: s a VCA.indication to the VCA Service user
at the receiving end to deliver a VCA_SDU.
NOTE – The VCA.indication primitive shall be the service indication primitive for the
18.104.22.168.2 Semantics The VCA.indication primitive shall provide parameters as follows:
VCA.indication 22.214.171.124.3 (VCA_SDU,
VCA Status Fields,
VCA_SDU Loss Flag (optional)) When Generated The VCA.indication primitive shall be passed from the service provider to the VCA Service
user at the receiving end to deliver a VCA_SDU.
126.96.36.199.4 Effect On Receipt The effect of receipt of the VCA.indication primitive by the VCA Service user is undefined.
188.8.131.52.5 Additional Comments
The VCA.indication primitive shall be used to deliver VCA_SDUs to the VCA Service user
identified by the GVCID.
3.5 VIRTUAL CHANNEL FRAME SECONDARY HEADER (VC_FSH) SERVICE 3.5.1 OVERVIEW OF VC_FSH SERVICE
The Virtual Channel Frame Secondary Header (VC_FSH) Service provides synchronous
transfer of fixed-length data units in the Transfer Frame Secondary Header (FSH) 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. CCSDS 132.0-B-1 Page 3-9 September 2003 CCSDS RECOMMENDATION FOR TM SPACE DATA LINK PROTOCOL 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.
3.5.2 VC_FSH SERVICE PARAMETERS
184.108.40.206 General The parameters used by the VC_FSH Service primitives shall conform to the specifications
contained in subsections 220.127.116.11 through 18.104.22.168.
22.214.171.124 FSH_SDU NOTE – The FSH_SDU parameter is the service data unit transferred by the VC_FSH
Service in the Frame Secondary Header of Transfer Frames of a Virtual Channel.
For restrictions on the FSH_SDU transferred by the VC_FSH Service, see 3.2.4.
126.96.36.199 GVCID The GVCID para...
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