HERE COMES SUMMER: After cracking mind-boggling ciphers for three weeks, sophomore reviews LMU cryptology course

(Photo used by permission of Zhang)
Sophomore Allison Zhang (second from right) at one of CTY’s Friday dances with a few girls from her hall in her dormitory.

Every summer SCDS students take courses on college campuses to expand their knowledge. In this series, “Here Comes Summer,” staffers review their courses.

With a fresh flip-flop tan, 30 new contacts in my phone and a mastery of cracking codes, I departed from Loyola Marymount University (LMU) in Los Angeles.

I was there June 26-July 15 for Johns Hopkins University’s Center for Talented Youth (CTY) summer program.

With sites all over the United States and even in Hong Kong, 12- to 16-year-olds can take three-week-long intensive summer classes on subjects like Logic, Cognitive Psychology,  Paleobiology, Game Theory and International Politics.  

I studied Cryptology, the art of writing and cracking ciphers, and loved every minute of it.

A friend who took the class last summer had strongly recommended it. So, with zero knowledge about cryptology, I decided to give it a try.

There were two sections of Cryptology, each with 15 students. Our instructor, Cody Gunton, was a fifth-year Ph.D. student in math at the University of Arizona.

In class, we focused on ciphers, which are ways of encrypting a message by replacing each character. A cipher is different from a code, which is another method of encryption where words or phrases are replaced by a predetermined code word.

We learned a new cipher almost every day. We would first determine its strengths and weaknesses as a method of communication. Then we practiced encoding and decoding a message using that cipher. Lastly, there would be practice ciphers we had to crack. Those were created specifically for this class by someone at the National Security Agency.

We also learned about the Enigma, a machine that the Germans used in World War II to encrypt their messages.

The Enigma had roughly 158 million million million (1.58 x 10^20) different starting settings that were chosen at random each day by the Germans. The day’s messages were then encrypted with those settings. However, if someone knew the starting settings, the messages would be easy to decipher.

And so, with the seemingly impossible task of determining the day’s settings, Alan Turing and other cryptanalysts at Bletchley Park in England set out to crack the Enigma.

Eventually, Turing built the Bombe, a machine that could determine the key given a short piece of the message. Had the Enigma not been cracked, historians estimate that the war would have lasted two to four more years.

We also learned about the one-time pad, which encoded a message by using a long key consisting of randomly generated characters. It’s called the one-time pad because people would have a pad of these keys, and the keys could be used only once.

In reality, utilizing the one-time pad isn’t practical because of the difficulty of generating truly random characters and preventing others from acquiring the keys.

However, it is the only known cipher that has been mathematically proven to be impossible to crack. It is currently being used to encrypt messages between Washington D.C. and Moscow.

(Photo used by permission of Zhang)
Sophomore Allison Zhang (top row, third from right) with her Cryptology class on the last day of the course. Her instructor, Cody Gunton, is in the top row, far right.

On the last day of CTY, there was a scavenger hunt.

We were broken up into 10 teams of three, and given encrypted clues that, when deciphered, gave the location of the next clue.

After three hours of running around campus, my group and two others were racing back to our classroom for the final cipher. It was an Enigma cipher that could be broken using a paper Enigma machine we had created earlier that week. Finally, after a few failed attempts and frustrated groans, my two teammates and I walked out of the classroom with a shiny new copy of “Sherlock Holmes” as a prize.

The living arrangements at CTY were similar to any residential summer camp. Students were divided into gender-specific halls in the dorms based on the classes they took. Typically, students in the same class would be in the same hall. A Residential Assistant (RA) was in charge of one hall.

Most of the CTY students live on campus in the dorms, but there were a few commuters.

Monday through Friday, the schedule barely changed. Breakfast was at 8 a.m. (each hall was given a breakfast time from 7:30-8:15 a.m. to try to lessen long lines. The lines were still long.)

From 9 a.m.-12:30 p.m., we had class, then one hour for lunch. Once again, there were different lunch times for each class to prevent long lines. Once again, it didn’t work.

Starting at 3:30 p.m., there were weekly activities ranging from swimming to silent reading to music practice.

There were also daily activities, which varied from day to day. These activities included The Dark Side of YouTube (where we watched YouTube videos for an hour), Korean Barbecue (where we made posters and paraded around the campus professing our love for Korean Barbecue) and Rock Appreciation (in which we discussed rock in all its forms, from rock music to The Rock to rock candy).

There were dances on Friday nights instead of an evening class. And on the weekends we could walk to the Ralphs supermarket about half a mile away.

During the three weeks, I attended about 100 hours of class. While I don’t plan on working for the Central Intelligence Agency, the class was still fascinating.

If someone asked me if I would recommend CTY or the Cryptology class, I would say yes in a heartbeat. The environment was welcoming, the people were kind and the class was engaging and thought provoking.

By Allison Zhang

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