Enigma 2 ~ 21

Enigma 2 ~ 21 Points

By: Emma Eisenhauer, Nicole Sichel, Miles Taylor,
Jonathan Ram, Eshaan Gandhi, and Nick Rinala

Authentication

Our box was never supposed to come back to Alice, so if it did we would
know that the Eves messed with it. The Bobs would know if the Eves had
messed with it because there should be nothing on the whiteboard, so if
there was the Eves had messed with it. Also, it didn't matter if there was
something on the whiteboard because we put everything on the
spreadsheet

Our code

We used the Diffie Hellman Exchange. Below is our system that we used on
the last day.

Diffie Hellman Exchange

1. Alice gets box
2. Alice tells Mrs. Carr to write the p: and g: on the spreadsheet.
3. Bob writes the p: and g: down on a piece of paper and tells Mrs. Sopko to
4. delete the p: and g: (so the Eves don’t know what it is.)
5. Alice works out the math and gets a number.
6. Alice tells Mrs. Carr to write the number on the spreadsheet.
7. Bob writes down Alice’s number and tells Mrs. Sopko to delete the number.
8. Bob works out the math and gets a number.
9. Bob tells Mrs. Sopko to write his number on the spreadsheet.
10. Alice writes down Bob’s number and tells Mrs. Carr to delete the number.
11. Alice does the math to get a secret key while Bob does the same math.
12. Alice puts the 3 digit key (the encrypted one) on the spreadsheet.
13. Bob tells Mrs. Sopko to delete it once it is written down.
14. Alice locks the box, switches the numbers on the lock around, writes
15. nothing on the whiteboard, and sends it.
16. When Bob gets the box he will get the post-it note out of the box and use
17. the method to open the box.

Highest Point Gain

We made our highest point gain on the last day. That day we started at
9 points before we started working with Diffie Hellman. With
Diffie Hellman, we made 12 points on the last day.

Our Key System

Our key system was public. We did Diffie Hellman and used the
spreadsheet to help us. The spreadsheet also allowed us to be more
efficient and authenticated. Also, the Eves couldn’t add to the
spreadsheet to mess us up, so it was safe.