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The effective size of a key in the Data Encryption Standard (DES) algorithm is 56 bits. Explain in words how to calculate the size of the DES keyspace. 

When using encryption for confidentiality which of the following should be kept secret?

Alice generates a pseudorandom key and uses it with a symmetric cipher scheme to encrypt a message for Bob.  Explain what she should do to send the key to Bob over an insecure communications channel (e.g. the Internet).

Suppose you browse to a website that presents a typical X.509 certificate chain, containing three (3) certificates.  The certificate at the bottom of the chain is for the website.  You browser shows that the certificate is verified.  Which of the following is/are true about the certificate at the top of the chain?

Counter mode encryption/decryption is relatively fast because …

A = 010110102B = 110000112C = A XOR B = 2

A security mechanism is called “specific” because …

Use u – substitution to find all solutions: . Type your answers as a comma – separated list. Type the smaller value first. Space once after the comma.

The following graph was created by horizontally shifting the graph of the basic function . Write a function that describes the graph. Do not include f(x)=. Use | for absolute value bars. Do not space. 

If you have not used the narrated PowerPoint for this chapter, write ‘Did Not Use’ as your answer. If you did, write 4-5 sentences that summarize what any Internal Discussion question(s) in it for this chapter asked you to write about. You cannot click over and check it now–if you do that activity will be recorded and you will have no grade for the quiz.