title: iSCSI data transport packet overhead
body: <p>This question is admittedly overlapping with <a href="https://stackoverflow.com/questions/7886594/iscsi-packet-header">iSCSI Packet Header</a> but I hope for a more specific answer than provided for that one for my more specific question.</p>
  
  <p>Question: How much overhead is introduced by iSCSI and SCSI in the transfer of the data to read or write? </p>
  
  <p>I understand that this is done in the Data-In and Data-Out transport packets and I understand there is overhead from TCP/IP and Ethernet, but what additional overhead is needed by iSCSI/SCSI? I recognize that SCSI Protocol Data Units (PDU) are packed into TCP datagrams by some algorithm, but I'm unsure of that algorithm.</p>
  
  <p>I realize there is a full conversation that needs to happen between the initiator and target and I will ignore that part. So, I only want to know about the data packets sent following a read or write command.</p>