Database System Concepts
7th Edition
ISBN: 9780078022159
Author: Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher: McGraw-Hill Education
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Chapter 9, Problem 11PE
Explanation of Solution
Effects:
- The major problem with digital certificates is that there is no way for withdrawing them.
- For example, a person “P” claims to be a staff member of an organization “O1” and obtains a new public key certified by the certifying authority “CA”.
- Assume the certifying authority “CA” believed incorrectly that “P” was acting on behalf of an organization “O2”, and it gave person “P” a certificate “cert”.
- Now, the person “P” can communicate with a person “V” who verifies the “cert” provided by “P” and trusts that the public key in “cert” really belongs to the organization “O2”.
- The person “P” can now communicate with “V” employing the public key and the person “V” trusts the communication is from the organization “O2”...
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Refer to page 80 for problems on white-box testing.
Instructions:
•
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Refer to page 20 for problems related to finite automata.
Instructions:
•
Design a deterministic finite automaton (DFA) or nondeterministic finite automaton (NFA) for the
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•
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