<!-- Created with blockdiag from the source below:

  seqdiag {
    default_note_color = aliceblue;

    client -> server [
        label = "start",
        leftnote = "transfer_id\ntype=TRANSFER_START"
    ];

    client <- server [
        noactivate,
        label = "set transfer parameters",
        rightnote = "transfer_id\noffset\nwindow_end_offset\ntype=PARAMETERS_RETRANSMIT\nmax_chunk_size\nchunk_delay"
    ];

    client -\-> server [
        noactivate,
        label = "requested bytes\n(zero or more chunks)",
        leftnote = "transfer_id\noffset\ndata\n(remaining_bytes)"
    ];

    client <-\- server [
        noactivate,
        label = "update transfer parameters\n(as needed)",
        rightnote = "transfer_id\noffset\nwindow_end_offset\ntype=PARAMETERS_CONTINUE\n(max_chunk_size)\n(chunk_delay)"
    ];

    client -> server [
        noactivate,
        label = "final chunk",
        leftnote = "transfer_id\noffset\ndata\nremaining_bytes=0"
    ];

    client <- server [
        noactivate,
        label = "acknowledge completion",
        rightnote = "transfer_id\nstatus=OK"
    ];
  }

-->
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  <title>blockdiag</title>
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