Name: _____________________

                                                 id#: _____________________


			 UNIX System Administration Exam 18 

Notes:
	No circular definitions please.
	Be very specific.
	All terms should be assumed to be in the context of UNIX. 
	Grading:
         	3 free points
         	1 point for each correct answer
        	-1 point for each incorrect, partial, or unintelligible answer
         	0 points for each unanswered question
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What is the purpose of the /etc/shadow file and what problem does it solve?





Exactly how does the "crack" program work?





What is the security risk posed by setuid programs?





What aspects of standard UNIX file permissions cannot be represented using
the access control matrix (ACL) concept?






Does SSH rely on the remote client's IP address for authentication?






How does a proxy firewall increase the security of the protected network?






Rick knows that Jane never lies.
Jane knows that Mike never lies.
Mike knows that Sara never lies.
Jane tells Rick that Mike told her that Sara told him that her dog died.
Should Rick believe the news?