The lesson plan for U4L9 suggests filling in a table that shows the terms around public key encryption (private key, public key, encrypted message, how to decrypt and how to crack) and how each analogy used (lockbox, cups & beans, public key crypto widget) applies. Does anyone have a key for this table? I have most of it, but I’d like to make sure I present it correctly.
Thanks,
Lesnie
Lockbox Cups & Beans Public Key Crypto Widget
Private key
Public key
Encrypted message
How to decrypt
How to crack
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I don’t have a key, but if you would like to share what you have through a personal message, I could look over it and see if we agree.
Hi @lesnie.orsborn,
It doesn’t look like code.org provides a key, but there’s a partial table of answers in one of the teacher documents linked in the lesson plan - titled “Public Key Bean Counting (Cups & Beans Activity)” - Teacher demonstration guide.
Thanks for responding. This is what I have. I think it’s (mostly) correct, but I’d appreciate any input.
Lesnie
Lockbox
Cups & Beans
Public Key Crypto Widget
Private key
The key to your private lockbox.
Alice’s secret number of beans
Alice’s private key.
Public key
Copy of the key that you shared with others to deposit messages into your lockbox
Alice’s secret beans seal inside a cup.
(NOTE: Alice isn’t encrypting a message to send but rather producing a key that others can use to send her a message.)
Alice’s public modulo.
Encrypted message
The messages dropped into the locked dropbox
Bob adding beans to Alice’s public cup. The “encrypted” cup of beans contains Bob’s secret message and Alice’s private key.
Bob’s secret number
How to decrypt
Use your private key to open the lockbox and read the messages.
Alice figuring out how many beans Bob added to the cup by knowing how many were there originally.
Alice can figure out Bob’s private number using her private key.
How to crack
Must have a copy of the private key
Hacker trying to count how many beans are in the container.
A hacker can attempt to figure out Bob’s secret number without the private key.
Thanks for your response. I did see some of the answer in code.org. This is what I came up with.
Lockbox
Cups & Beans
Public Key Crypto Widget
Private key
The key to your private lockbox.
Alice’s secret number of beans
Alice’s private key.
Public key
Copy of the key that you shared with others to deposit messages into your lockbox
Alice’s secret beans seal inside a cup.
(NOTE: Alice isn’t encrypting a message to send but rather producing a key that others can use to send her a message.)
Alice’s public modulo.
Encrypted message
The messages dropped into the locked dropbox
Bob adding beans to Alice’s public cup. The “encrypted” cup of beans contains Bob’s secret message and Alice’s private key.
Bob’s secret number
How to decrypt
Use your private key to open the lockbox and read the messages.
Alice figuring out how many beans Bob added to the cup by knowing how many were there originally.
Alice can figure out Bob’s private number using her private key.
How to crack
Must have a copy of the private key
Hacker trying to count how many beans are in the container.
A hacker can attempt to figure out Bob’s secret number without the private key.