Description: A counter that increments every time a PTP message is discarded, caused by the occurrence of any of the following conditions:

a) A received Announce message is not qualified, denoted by the function qualifyAnnounce (see 10.3.10.2.1 and 13.1.3.4) of the PortAnnounceReceive state machine (see 10.3.10 and Figure 10-12) returning FALSE; b) A Follow_Up message corresponding to a received Sync message is not received, denoted by a transition of the condition (currentTime greater or equal to followUpReceiptTimeoutTime) to TRUE from FALSE when in the WAITING_FOR_FOLLOW_UP state of the MDSyncReceiveSM state machine (see 11.2.13 and Figure 11-6); c) A Pdelay_Resp message corresponding to a transmitted Pdelay_Req message is not received, denoted by a transition from the WAITING_FOR_PDELAY_RESP state to the RESET state of the MDPdelayReq state machine (see 11.2.15 and Figure 11-8); d) A Pdelay_Resp_Follow_Up message corresponding to a transmitted Pdelay_Req message is not received, denoted by a transition from the WAITING_FOR_PDELAY_RESP_FOLLOW_UP state to the RESET state of the MDPdelayReq state machine (see 11.2.15 and Figure 11-8).