Figure C-6 depicts the data flow for the Verify/Validate Command process. Authenticated commands are passed to Check Command Decoder. This process uses information from Command Info DB to determine the expected decoder status for the command. The command function is then evaluated by Evaluate Command Function process. This function reads the Command Evaluation KB data store, which contains the knowledge base or procedure to be used to perform the functional verification. The following describes the processes identified in Figure C-6.
Check Command Authentication - This function analyzes command response for correct SV authentication. It inputs an identifier of the command to be authenticated, the vehicle command count, and the ground command count. It interrogates the status of the authentication check and sends the status to the satellite operator. It also generates an output request to resolve commands that fail the check and passes authenticated commands to the Check Command Decoder function.
Check Command Decoder - This function checks command responses for correct decoder status. It inputs an identifier of the authenticated command and the decoder status. It also inputs decoder information from the Command Info database. The function generates the status of the command decoder check and sends it to the satellite operator. It also generates an output request to resolve commands that fail the check and passes the decoded commands to the Verify Command Function process.
Verify Command Function - This function performs the functional verification of the command response. It inputs an identifier of the command, the command evaluation procedure or knowledge base, and telemetry data. It outputs the status of the functional verification and sends it to the satellite operator. It also outputs a request to resolve any commands that fail the verification.