Msg : File_Request   -- client to file server
  Type       Read
  File_ID    44
  Offset      0
  Size       400
  Program    50

Msg : File_Response  -- file server to client
  Type       Read
  File_ID    44
  Program    50
  Status     Request_ACK

Msg : Get_File        -- server to storage device
  Type       Read
  File_ID    44
  Offset      0
  Size       400
  Address    1AF3000

Msg : File_Data       -- server to client
  Data       0000
  ...
  Data       FEF2

Msg : Get_File_Response   -- storage device to server
  File_ID    44
  ACK_NACK   Complete


Msg : Get_File_Response   -- server to client
  File_ID    44
  ACK_NACK   Complete

Msg : File_Response  -- file server to client
  Type       Read
  File_ID    44
  Program    50
  Status     Complete