An interrupted file transfer (e.g. for bad propagation or power outage, the same case), whenever the connection is restored, it is starting again from byte 0. That's not a matter of protocol (Vara), indeed on my humble opinion should be managed by the application, for the couple sender/receiver and buffering the file on the sender side.
Is there any way to recover the file from the point where interrupted?
IZ2RLJ - Elio
Back in the days of BBS and phone lines. We used Z modem. We could reconnect and start where it let go. It was something like that.