title: Where exactly a timestamp is set?
body: <p>I need to know at what exact point the timestamp for receiving or sent frames on a NIC is set. I have already searched a lot, but i can't find anything, which really helped me.
  For the sending-case it could be for example:</p>
  
  <ul>
  <li>when the first Bit left the network cable</li>
  <li>when the last Bit left the network cable</li>
  <li>when the frame data was written into buffer</li>
  </ul>
  
  <p>I am using a Intel 82541PI-Network Card.</p>