1 3 for restrictions on the tm transfer frames

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Unformatted text preview: rough which the Frame is to be transferred. NOTE – The GVCID parameter is the SAP address of the VCF Service. 3.7.2.4 Frame Loss Flag The Frame Loss Flag is an optional parameter that may be used to notify the user at the receiving end of the VCF Service that a sequence discontinuity has been detected, and that one or more Transfer Frames of the specified Virtual Channel have been lost. If implemented, the flag shall be derived by examining the Virtual Channel Frame Count in the Transfer Frames. 3.7.3 VCF SERVICE PRIMITIVES 3.7.3.1 General The service primitives associated with the VCF Service are: a) VCF.request; b) VCF.indication. 3.7.3.2 VCF.request 3.7.3.2.1 Function At the sending end, the VCF Service user shall pass a VCF.request primitive to the service provider to request that a Frame be transferred to the user at the receiving end through the specified Virtual Channel. NOTE – The VCF.request primitive is the service request primitive for the VCF Service. 3.7.3.2.2 Semantics The VCF.request primitive shall provide parameters as follows: VCF.request CCSDS 132.0-B-1 (Frame, GVCID) Page 3-16 September 2003 CCSDS RECOMMENDATION FOR TM SPACE DATA LINK PROTOCOL 3.7.3.2.3 When Generated The VCF.request primitive shall be passed to the service provider to request it to send the Frame. 3.7.3.2.4 Effect On Receipt Receipt of the VCF.request primitive shall cause the service provider to transfer the Frame. 3.7.3.2.5 Additional Comments The VCF.request primitive is used to transfer Transfer Frames of a Virtual Channel across the space link. 3.7.3.3 VCF.indication 3.7.3.3.1 Function At the sending end, the service provider shall pass a VCF.indication to the VCF Service user at the receiving end to deliver a Frame. NOTE – The VCF.indication primitive is the service indication primitive for the VCF Service. 3.7.3.3.2 Semantics The VCF.indication primitive shall provide parameters as follows: VCF.indication 3.7.3.3.3 (Frame, GVCID, Frame Loss Flag (optional)) When Generated The VCF.indication primitive shall...
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This document was uploaded on 03/06/2014.

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