Exercises: Legal and Ethical Concerns, and Safe Computing

1. a) Who automatically owns the copyright to a photograph that Mia takes?

1. b) What does a Creative Commons license do for the creator and for people who want to use the work?

Personally identifiable information (PII) is information that can be used to identify, contact, or locate a specific person. Which of these are PII? Explain each answer.

1. i) Full name and home address

ii) Favorite color

iii) Social Security number

iv) The fact that a user likes pizza

Multi-factor authentication (MFA) requires two or more different kinds of proof of identity. Which of these is MFA? Explain.

1. i) A password and then a second password.

ii) A password and then a code sent to the user's phone.

iii) A very long password.

Mateo wants to use a song in an online video that will show ads and earn money. He finds three songs with these licenses:

• Song 1: all rights reserved

• Song 2: Creative Commons BY (attribution required)

• Song 3: Creative Commons BY-NC (attribution required, non-commercial use only)

1. a) For each song, say whether he may use it in his video and what he must do.

1. b) Which song would be a problem even if he gives credit, and why?

Sophia sends a private message to a website. The browser shows a padlock because the connection uses public-key encryption.

1. a) Explain the difference between symmetric encryption (one shared key) and public-key encryption (a public key and a private key).

1. b) Which key does the website publish, and which key does it keep secret?

1. c) Why does public-key encryption let strangers communicate securely without having met first?

An attacker uses brute force, trying every possible password. Compare the number of possibilities for each type:

1. i) A 4-digit PIN (digits 0-9)

ii) An 8-character password using only lowercase letters

iii) An 8-character password using lowercase letters, uppercase letters, and digits

1. a) Compute the number of possible passwords for each. Write the last two in scientific notation, rounded to three significant figures.

1. b) Explain what these numbers show about password length and variety.

1. c) Why is reusing the same password on several websites dangerous even if the password is strong?

Chloe builds a free study app for her high school. The app asks users for their full name, school, phone contacts, and real-time location. Its privacy policy says that the data may be shared with "partners."

1. a) Identify which of the collected items are PII, and explain which ones the app probably does not need to work.

1. b) Describe two privacy risks: one if the data are sold to third parties and one if the app's database is breached.

1. c) Recommend four changes (to what is collected, how it is stored, and what users are told) that would reduce the risks, and explain each.

Ethan is waiting at the airport and connects to a free public Wi-Fi network named "Airport_Free_WiFi" to check his bank account.

1. a) Describe two ways an attacker could steal his information on this network (for example, an imitation network or intercepted traffic).

1. b) Rank these protections from most to least helpful here and justify your ranking: using a VPN, checking that the bank's website uses HTTPS, enabling MFA, and using his phone's cellular data instead.

1. c) Explain one risk that remains even when he uses HTTPS and a strong password, such as phishing or malware on his device.