1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +---------------+---------------+-------------------------------+
   |     Type      |     Length    |             Value  ...        |
   +---------------+---------------+-------------------------------+
   //              ...   (optional) Value                         //
   +---------------------------------------------------------------+