@ManagedOperation(description="Purges highes delivered messages and compacts the retransmission tables")
public void purgeAndCompact() {
for(Map.Entry<Address,ReceiverEntry> entry: recv_table.entrySet()) {
NakReceiverWindow win=entry.getValue().received_msgs;
win.stable(win.getHighestDelivered());
win.compact();
}
}
public void resetStats() {