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6.9: Summary

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    As computing and networking resources have become more an integral part of business, they have also become a target of criminals. Organizations must be vigilant with the way they protect their resources. The same holds true for individuals. As digital devices become more intertwined in everyone’s life, it becomes crucial for each person to understand how to protect themselves.

    Study Questions

    1. Briefly define each of the three members of the information security triad.
    2. What does the term authentication mean?
    3. What is multi-factor authentication?
    4. What is role-based access control?
    5. What is the purpose of encryption?
    6. What are two good examples of a complex password?
    7. What is pretexting?
    8. What are the components of a good backup plan?
    9. What is a firewall?
    10. What does the term physical security mean?


    1. Describe one method of multi-factor authentication that you have experienced and discuss the pros and cons of using multi-factor authentication.
    2. What are some of the latest advances in encryption technologies? Conduct some independent research on encryption using scholarly or practitioner resources, then write a two- to three-page paper that describes at least two new advances in encryption technology.
    3. Find favorable and unfavorable articles about both blockchain and bitcoin. Report your findings, then state your own opinion about these technologies
    4. What is the password policy at your place of employment or study? Do you have to change passwords every so often? What are the minimum requirements for a password?
    5. When was the last time you backed up your data? What method did you use? In one to two pages, describe a method for backing up your data. Ask your instructor if you can get extra credit for backing up your data.
    6. Find the information security policy at your place of employment or study. Is it a good policy? Does it meet the standards outlined in the chapter?
    7. How diligent are you in keeping your own information secure? Review the steps listed in the chapter and comment on your security status.


    1. The Caesar Cipher. One of the oldest methods of encryption was used by Julius Caesar and involved simply shifting text a specified number of positions in the alphabet. The number of shifted positions is known as the key. So a key = 3 would encrypt ZOO to CRR. Decrypt the following message which has a key = 3: FRPSXWHU
    2. The Vigenere Cipher. This cipher was used as recently as the Civil War by the Confederate forces. The key is slightly more complex than the Caesar Cipher. Vigenere used the number of letters after ‘A’ for his key. For example, if the key = COD, the first letter in the cypher is shifted 2 characters (because “C” is 2 letters after the letter ‘A’), the second letter is shifted 14 letters (O being 14 letters after ‘A’), and the third letter is shifted 3 letters (D being 3 letters after ‘A’). Then the pattern is repeated for subsequent letters. Decrypt the following message which has a key = COD: YSPGSWCHGCKQ
    3. Frequency and Pattern Analysis. If you’ve ever watched Wheel of Fortune you know that contestants look for patterns and frequencies in trying to solve a puzzle. Your job in this lab is to analyze letter frequency and letter patterns to determine the plaintext message which in this case is a single word. The key is a simple substitution where the same letter in plaintext always results in the same letter in the cyphertext. The most frequently used letters in the English language are: E, A, O , I, T, S, N. Pattern analysis includes knowing words that have double letters such as “school.” Other patterns include “ing” at the end of a word, “qu” and “th” as a pairs of letters.Cyphertext = CAGGJWhat is the key and the plaintext?

    1. Gallagher, S. (2012, November 3). Born to be breached. Arstechnica. Retrieved from
    2. SANS Institute. (n.d.). Information Security Policy Templates. Retrieved from on May 31, 2013.
    3. SANS. (n.d.). SCORE: Checklists and Step by Step Guides. Retrieved from
    4. Iansiti, M. and Lakhani, K. R. (2017, January). The truth about blockchain. Harvard Business Review. Retrieved from
    5. Wikipedia. (n.d.). Bitcoin. Harvard Business Review. Retrieved from
    6. Fernandes, B. (2017, October 20). Personal telephone interview

    This page titled 6.9: Summary is shared under a CC BY-SA license and was authored, remixed, and/or curated by David T. Bourgeois (Saylor Foundation) .

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