Cryptography is the process or skill of communicating in secret writing also known as encryption (Webster, p.475). Encryption is a method of scrambling data in some manner in expectance of data transmission (Webster, p.475). Encryption seems like a recently discovered method because of advancements in computers, but it has been traced back to hundreds of years ago. More recently, in periods of war, the use of encryption became dominant so the messages were not intercepted by the opposing forces. With the advancements of technology, the need for security and tighter control on how we send information electronically over the internet or through a network also needs to advance. A deeper look into cryptography, cryptanalysis, and the Data Encryption Standard (DES) will provide a better understanding of data encryption.
There are a number of different ways to protect data during transformation, such as substitution, character for character replacement, the spartan scytale, transposition ciphering, rail-fence ciphering, paper and pen ciphering, and finally the most recent algorithmic encryption.
History.
Cryptography has been traced back thousands of years ago. The spartan scytale is a historical method to send a secret message that has been traced back 2500 years ago (Beutelspacher, p.3). Using this method, the send and receiver have the same scytale, or object of the same radius. The sender would wind ribbon around this cylinder and write on it lengthwise. When unwound, one was unable to read the message. Upon delivery, the receiver winds the ribbon on his or her cylinder to read it.
A more modern method to secretly send a private message is character replacement (Beutelspacher, p.5). In this case the sender and receiver have the same table of character replacements. The sender encodes the message with his table to a form that is unreadable without knowing the character replacements.