Big Data and Privacy

Big Data and Privacy

1. Big Data

   • The idea that computers are gaining and using more and more data
   • Moore's Law
     • The law that states that every two years, computers become twice as efficient/smart

2. Encryption/Decryption

   • Encryption is the act of turning a message into a puzzle and decryption is the act of solving said puzzle
   • Caesar Cipher
     • A cipher that involves shifting the alphabet by a specific number.  For example, a could become b and b could become c
   • Substitution Cipher
     • A cipher where every letter is actually another letter.  Sort of like the Caesar Cipher where every one letter is going to be another every time it appears
     • Frequency Analysis
       • An analysis of how often a letter appears in the human language.  For example, the letter E is the most common letter in the English language, so replacing the most common letters in the message to the letter E and going down to the least common letters, you can solve for the letters that don't match up.
   • Vigenere Cipher
     • This one works almost like a graph in math, where the alphabet (space included) are the numbers on the x and y axis.  A key (sort of a password) is used for the X axis, while the letter in the message being encrypted is the Y axis.  
     • Public Key Cryptography
       • Any cipher that works similarly to the Vigenere Cipher.  While the instructions to use these ciphers are available to everybody, the key to solve the cipher is only between the sender and the reciever, which makes it much harder to crack
       • Encryption Key
         • The key used to solve any public key cryptography cipher
       • Computationally Hard
         • Something that even a computer would find difficult to solve.  A good example is a password: a computer can go through every possible combination to figure out a password, but if the password is long enough it would take hears, even millennia to solve.
       • Asymmetric Encryption
         • When some part of an encryption (a key for example) is split into parts to make it harder to solve.  In our modulo clocks, the first part was split into multiplication to make it harder for the eavesdropper to find out
   • Encryption Algorithm
     • The process used to encrypt/decrypt a message