title: Fail-safe importing data: Matching term?
body: <p>I am searching the matching term for this problem:</p>
  
  <p>System-1 has a directory containing files.</p>
  
  <ol>
  <li>system-1 sends the data to system-2</li>
  <li>system2 imports the data.</li>
  <li>system-2 sends an acknowledgement to system-1</li>
  <li>system-1 deletes/moves the local data</li>
  </ol>
  
  <p>A power-failure or bug can happen every time.</p>
  
  <p>If the acknowledgement gets lost, then system-1 will try to send the data again.</p>
  
  <p>Now the data gets imported twice, which is a failure. Data should get imported once.</p>
  
  <p>This question is not about a solution to the issue, this question is about how to call this problem.</p>
  
  <p>What is the matching term for this?</p>
  
  <p>Example: System-1 could be a mail-server and system-2 could be an issue system which imports mails.</p>