Skip To Top Navigation Skip To Content Skip To Footer
FSU Math Department Hosts "History of Secrets, Cryptography and Privacy" Impact
Fairmont State News

FSU Math Department Hosts "History of Secrets, Cryptography and Privacy"

Nov 14, 2016

The Fairmont State University Math Department recently hosted a guest speaker, Dr. Patrick Juola, a professor of computer science from Duquesne University, who gave a lecture titled "The History of Secrets: Cryptography and Privacy.”

The main theme of his talk was that we use cryptography to hide "secrets" from "bad guys" -- but what a "secret" is and who the "bad guy" is depends on context. This can be as innocent as hiding your grades from your parents, hiding your credit card information from hackers or as serious as obscuring the plan for a terrorist attack from the police. The discussion of cryptography leads to many interesting mathematical and political questions.

Juola's lecture discussed the history of cryptography from ancient to modern times. He begin with the so-called "Caesar cipher," named after the Roman general Julius Caesar who used the cipher to hide his messages from his enemies. Caesar ciphers are the foundation of "secret decoder ring" toys; the process works by replacing each letter in a secret message one-to-one with other letters. After that, Juola discussed the "Vigenère cipher" (circa the 16th century) which links together multiple Caesar ciphers to encrypt data.

The Vigenère cipher was thought to be unbreakable ("le chiffre indéchiffrable") until the late 19th century. In the first half of the 20th century, cryptography was used by all armies during the world wars. Famously, the "Engima machine" was used by the Nazis to encrypt their messages. The British mathematician Alan Turing (recently popularized in the movie "The Imitation Game") broke the Nazis' cryptography which led to the Allies being able to read their secrets to get a military advantage.

All of these old encryption methods are now useless -- a common cell phone can decrypt them in seconds. This led to more modern methods of encryption that are more resistant to decryption by computers. The "data encryption standard" (DES) was defined in 1976 by the National Security Agency (NSA) as the official encryption method of the government of the United States. However in the late 1990s, DES was shown by researchers to be theoretically insecure. This lead to the modern "advanced encryption standard" (AES) which became the standard encryption for use by the United States government in 2002.

 From Caesar's time to modern day, encryption has been intimately tied with military applications. Until 1992 "Information Security Systems and equipment, cryptographic devices, software and components" were restricted in the "United States Munitions List" for export out of the country. These rules were eventually relaxed. This led to the use of cryptographic methods by the average citizen to keep personal information secure from hackers.

Everyone who uses the internet uses cryptography in some way: any time you use a credit card online or see "https" at the beginning of a website URL (not just "http"), there is encryption involved.

The ability to hide information is not necessarily a universal good. During the aftermath of the December 2015 San Bernardino terrorist attack, the FBI asked Apple to decrypt an iPhone tied to the suspects. The iPhone potentially contained information that was obscured by the strong encryption built into the phone, and so whatever information that existed was not easily accessible. Apple refused to help the FBI decrypt the iPhone, citing the security of their customers. This event brought the political questions of cryptography into public discussion.

Juola's lecture ended with some food for thought. Should every human have the right to strong cryptography and be able to hide secrets? If not, how should they be restricted? Is it mathematically possible to have a cryptographic system that is breakable by the police but not by citizens (a "back door")? Is security more important than privacy?

College of Science and TechnologyDepartment of MathematicscryptographyDr. Patrick Juola