To do: April 18

• Grab a coin! (dime, quarter, penny, etc)
• Take out your IN.
• Pick up a handout.

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Safe Computing MC Practice #2: Which of the following best explains how symmetric encryption algorithms are typically used?

• Symmetric encryption uses a single key that should be kept secret. The same key is used for both encryption and decryption of data.
• Symmetric encryption uses a single key that should be made public. The same key is used for both encryption and decryption of data.
• Symmetric encryption uses two keys that should both be kept secret. One key is used for encryption, and the other is used for decryption.
• Symmetric encryption uses two keys. The key used for encryption should be made public, but the key used for decryption should be kept secret.

Safe Computing MC Practice #2: Which of the following best explains how symmetric encryption algorithms are typically used?

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• Symmetric encryption uses a single key that should be kept secret. The same key is used for both encryption and decryption of data.
• Symmetric encryption uses a single key that should be made public. The same key is used for both encryption and decryption of data.
• Symmetric encryption uses two keys that should both be kept secret. One key is used for encryption, and the other is used for decryption.
• Symmetric encryption uses two keys. The key used for encryption should be made public, but the key used for decryption should be kept secret.

Safe Computing MC Practice #3: In public key cryptography, the sender uses the recipient’s public key to encrypt a message. Which of the following is needed to decrypt the message?

A) The sender’s public key

B) The sender’s private key

C) The recipient’s public key

D) The recipient’s private key

Safe Computing MC Practice #3: In public key cryptography, the sender uses the recipient’s public key to encrypt a message. Which of the following is needed to decrypt the message?

A) The sender’s public key

B) The sender’s private key

C) The recipient’s public key

D) The recipient’s private key

Simulations

• Computer simulations are used to model real-world phenomena on a computer and has changed countless fields.
• Scientists from all disciplines rely on computer simulation, rather than real-life experiments, to rapidly test their hypotheses in simulated environments.

More on Simulations

Programmers might simulate:

• users moving across their sites to ensure they can handle spikes in traffic
• video game and virtual reality technology is built around the ability to simulate some aspects of the real world.

The speed and scale at which simulations allow ideas to be tested and refined has had far-reaching impact, and it will only continue to grow in importance as computing power and computational models improve.

Hypothesis

Flip a coin until you get 5 total heads. How many flips did it take? ���

Hypothesis

1. The most flips it took someone (including you) to get 5 total heads __________

�2. The fewest flips it took someone (including you) to get 5 total heads __________�

Actual (Experimental) Data

1. The most flips it took someone (including you) to get 5 total heads __________

�2. The fewest flips it took someone (including you) to get 5 total heads __________�

Hypothesis

What if you flipped a coin until you got 10,000 total heads. How many flips do you think it would take?�3. The most flips I think it would take someone to get 10,000 total heads: __________

�4. The fewest flips I think it would take someone to get 10,000 total heads __________�

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Simulation

How would we simulate the flipping of a coin?

Program: let's look at the results of the simulation of this experiment: the experimental data

Click on link in Hub

https://studio.code.org/projects/applab/VBg87lUXG7kVYAHPf6JBYuZNBp1ofsC-Auj4KVC9wrE

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Updating your Hypothesis

1. How close were your guesses on the high and low bounds for the number of flips to get 10,000 heads?

2. Were you at all surprised by this result? If they were different from what you predicted why might this be the case?�

Importance of Simulations

• Simulations are an increasingly important tool for a variety of disciplines.
• Weather and traffic predictions are based on computer models that simulate weather patterns or people moving through a city.
• Scientific research, whether in physics, chemistry, or biology, increasingly uses simulations to develop new hypotheses and test ideas before spending the time and money to run a live experiment.

Go over homework:

• Submit today's notes (warm-up and definition)
• AP Classroom - Safe Computing practice problems #1-12
• Complete online
• Show work for each question in IN
• Submit work to Hub

Rogue access point: a wireless access point that gives unauthorized access to secure networks. Data sent over public networks can be intercepted, analyzed, and modified.

https://www.professormesser.com/security-plus/sy0-501/rogue-access-points/

https://xkcd.com/936/

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Takeaway:

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A good password is easy to remember for the user, but hard for someone else (unauthorized) to guess based on knowledge they have about you.

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Unit 10 Lesson 10 - Warm Up

How good is your password?

• Cracking a password means that the number of possible keys must be so large, that even a computer trying billions of possible keys per second is unlikely to arrive at the correct key in a reasonable amount of time.
• Choosing a good password is meaningful because we want the key to be hard for a computer to guess.

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Hard for a computer!

• We know that a good encryption algorithm reduces the problem of cracking it to simply guessing the key.
• We want the key to be Computationally Hard to guess - in other words, hard for a computer to guess.
• Computationally Hard typically means that arriving at the solution would take a computer a prohibitively long time - as in centuries or eons.

What makes a secure password?

https://howsecureismypassword.net

Please do NOT use your real password.

Unit 10 Lesson 10 - Warm Up

https://howsecureismypassword.net

1. Create a few passwords using 8 lowercase ASCII characters (a-z). What’s the longest amount of time-to-crack you can generate?

2. Using any characters on the keyboard, what’s the longest amount of time-to-crack you can generate with an 8-character password?

3. As you try passwords, what seems to be the single most significant factor in making a password difficult to crack? Why do you think this is?

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https://howsecureismypassword.net

Complete #4 and 5

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What can I do to protect my data?

Unit 10 Lesson 10 - Activity

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• Use Multifactor Authentication

Single Factor Authentication

Unit 10 Lesson 10 - Activity

Example:

Password

Something you know

Two Factor Authentication

Unit 10 Lesson 10 - Activity

Example:

Password

Example:

Phone

Something you know

Something you possess

Multifactor Authentication - at least two of these:

Unit 10 Lesson 10 - Activity

Example:

Password

Example:

Phone

Something you know

Something you possess

Example:

Fingerprint

Something you are

What can I do to protect my data?

Unit 10 Lesson 10 - Activity

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• Use Multifactor Authentication
• Update Your Software

Unit 10 Lesson 10 - Wrap Up

Vocabulary:

Multifactor Authentication: a method of computer access in which a user has to successfully provide evidence in at least two of the following categories: knowledge (something they know), possession (something they have), and inherence (something they are). Each step provides a new layer of security.

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Computer Virus Scanning Software: protects a computing system against infection.

Safe Computing MC Practice: Which of the following best exemplifies the use of multifactor authentication to protect an online banking system?

A) When a user resets a password for an online bank account, the user is required to enter the new password twice.

B) When multiple people have a shared online bank account, they are each required to have their own unique username and password.

C) After entering a password for an online bank account, a user must also enter a code that is sent to the user’s phone via text message.

D) An online bank requires users to change their account passwords multiple times per year without using the same password twice.

Safe Computing MC Practice: Which of the following best exemplifies the use of multifactor authentication to protect an online banking system?

A) When a user resets a password for an online bank account, the user is required to enter the new password twice.

B) When multiple people have a shared online bank account, they are each required to have their own unique username and password.

C) After entering a password for an online bank account, a user must also enter a code that is sent to the user’s phone via text message.

D) An online bank requires users to change their account passwords multiple times per year without using the same password twice.

Prompt:

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What strategies do you use when creating a good password?

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Note: Please don't actually reveal any of your current passwords in your response.

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Unit 10 Lesson 10 - Warm Up

Homework

• Submit passwords handout
• Write 3 new key words and definitions in your IN glossary
• simulations, multi-factor authentication, computer virus scanning software

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Mock exam part 1 tomorrow (Tuesday)

Mock exam part 2 on Wednesday

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