Indication primitive note in addition to the reason

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Unformatted text preview: 232.1-B-2 Page 4-4 September 2010 RECOMMENDED STANDARD FOR COMMUNICATIONS OPERATION PROCEDURE-1 Table 4-4 lists the reasons for the ‘Alert’ notification. The Reason Code is carried by the parameter Notification Qualifier of the Async_Notify.indication primitive. NOTE – In addition to the Reason Code, an implementation may choose to include parameters giving the FOP Event number that caused the ‘Alert’ and the FOP State at the time of the Event. The additional information may assist the higher layers. Table 4-4: Reasons for the ‘Alert’ Notification Reason Reason Code Allowed number of transmissions exhausted for a Type-AD Transfer Limit or T1 Frame. • In case a CLCW arrives which negatively acknowledges a frame when Transmission_Limit is set to 1, FOP-1 generates an ‘Alert[limit]’. • In case the Timer expires and the value of the Transmission_Count has reached the value of the Transmission_Limit, FOP-1 generates an ‘Alert[T1]’. (Note: This ‘Alert’ Indication cannot occur if the Timeout_Type variable is set to ‘1’.) Allowed number of transmissions exhausted for a Type-BC Transfer T1 Frame derived from a Directive (e.g., ‘Initiate AD Service’ Directive with ‘Unlock’ or with ‘Set V(R)’). Lockout detected. Lockout CLCW with ‘Retransmit’ Flag = 0 and N(R) = NN(R) has arrived, when Synch last CLCW showed ‘Retransmit’ Flag = 1. All Transfer Frames sent are acknowledged but ‘Retransmit’ Flag = 1. Synch An attempt to acknowledge Transfer Frames is made during the Synch initializing phase corresponding to State (S4). CLCW with invalid N(R) has arrived. NN(R) CLCW with ‘Wait’ Flag = 1 and ‘Retransmit’ Flag = 0 has arrived. CLCW CLCW with invalid pattern of bits has arrived. CLCW FOP-1 and Lower Procedures are out of synchronization (Lower LLIF (Lower Procedures rejects Transfer Frame even though appropriate ‘Out’ Flag Layer Interface) is set to ‘Ready’). A ‘Terminate AD Service’ Directive has arrived CCSDS 232.1-B-2 Page 4-5 Term September 2010 RECOMM...
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This document was uploaded on 03/06/2014.

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