The nfdump project is distributed under the BSD license:

  Copyright (c) 2014, Peter Haag
  Copyright (c) 2009, Peter Haag
  Copyright (c) 2004-2008, SWITCH - Teleinformatikdienste fuer Lehre und Forschung
  All rights reserved.
  
  Redistribution and use in source and binary forms, with or without 
  modification, are permitted provided that the following conditions are met:
  
   * Redistributions of source code must retain the above copyright notice, 
     this list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above copyright notice, 
     this list of conditions and the following disclaimer in the documentation 
     and/or other materials provided with the distribution.
   * Neither the name of the author nor the names of its contributors may be 
     used to endorse or promote products derived from this software without 
     specific prior written permission.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
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  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
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