ndis miniport driver: miniportsendpackages

hi, I am learning ndis miniport driver. the nic card is not available temporarily, I would like to

  1. discard the packets or
  2. cache the packets and send them later.

If I would discard the packets, in MPSendPackets, how do I notify NDIS that the packages are sent? I do not see return value(s)? or is there any NDISxxx api I would need to call

on cache the packets, is there a sample in WDK I can take a look?

Thanks in advance