I see some of the IERs reported as Undelivered. Where did they go?
The IERs are reported as Undelivered when they do not make it to the destination before the simulation completes. There can variety of reasons for this including:
a. Lossy networks: The packets are dropped in the network without intimation to the host
b. Transport Layer: If the transport layer is not reliable the packets dropped in the network are never retransmitted and the IERs are counted as miscellaneous
c. Delays: Higher delays in the network may cause the simulation to be completed before some of the IERs can actually reach the destination. Changing the end time of the simulation or the IER stop times can ensure that the IER has ample time to reach the destination before the simulation ends.