Bibliography
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Firewalls and Internet Security by Bill Cheswick and Steve Bellovin 
 
- Ross Anderson.
Security Engineering: A Guide to Building Dependable Distributed Systems,
  pages 374–378.
John Wiley & Sons, New York, 2001.
 
- Dieter Gollmann.
Computer Security, pages 224–242.
John Wiley & Sons, New York, 1999.
 
- Eric Rescorla.
SSL
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Addison-Wesley, 2001.
 
- Elizabeth Zwicky, Simon
  Cooper, and D. Brent Chapman.
Building Internet Firewalls.
O'Reilly and Associates, Sebastopol, CA, second edition, 2000.