IST 323 The history of Information Security

Development of Information Security

Here, I want to add a summary for the development of information security.

People began to protect the information they wanted to deliver when people invented characters. The proposal to protect information is to protect a secret or avoid misunderstanding. Under this condition, whisper, notes, expression in one’s eyes can all be considered as a kind of information security because all these ways to deliver information can be executed in more liberal ways. Like we can talk out loudly instead of whispering, we can post a paper instead of a little note and we can also talk instead of eye contacting. However, if these public methods to protect information came to the stage of history, how would the real information security work?

Steganography

In the history of information security, the way to assurance the security is developed with the development of technology, especially information technology. I think the history of information security can be separated to four parts.

1.      Classical Encryption Era (BC – Early 20^th Century)

2.      Modern Times of Encryption (1920s – 1940s)

3.      Modern Encryption Era (1940s – 1960s)

4.      Network Security Era (  Till now)

During the classical encryption era, people encrypt information manually. Manual encryption has low efficiency so that only high level information would be encrypted, like military intelligence. During that time, the most famous method of encryption was Caesar Cipher. Also, ancient Greek wrote characters on the wooden backing of a wax tablet before applying its beeswax surface to achieve steganography. Chinese people wrote the information in poems in ancient times. The information they wanted to deliver was every first letter of each line of a poem, but the whole poem was not related to the information so that others would not notice the information. Also, during Civil War, the Federal Army widely used code books to protect the information.

The Era of Classical Encryption was long. The development was slow because people did not invent a new way to store information. Since human can only write the characters on paper, we could not have an advanced way to protect the information. However, since our technology developed, how would the next three eras look like?

I will talk about the other eras in the next blog. 

Stories in Information Security #2 _ World War Two

Enigma

As long as people had invented characters, people have found the importance to protect the information the want to transmit, especially during the war time. All the empires wanted to protect the information. For Caesar, he invented the cipher method to protect what his strategy. For Sparta, they write the text on a stripe of sheepskin which circle on a wooden stick, then move the stick to protect the information. All these method are processed by human beings so that there will always be some artificial mistakes. Before the ending of World War One, Arthur Scherbius who was a electronic engineer from Germany. He invented a mechanical cipher machine in the year of 1918. He was so proud of this machine and named it Enigma. From that time, human began to encrypt information through machine. This was a significant improvement in the history of information security. During World War Two, German deployed 30 thousands Enigma for army. Although Enigma was a significant improvement, it still used the substitution cipher method which was almost the same method with Caesar Cipher. However, since Enigma was a cipher machine, it can list much more cipher solution than human can list. Based on the principle of Enigma, it can provide 10 to 114 square possibilities. Even after the Alliance captured several Enigma and learned the principle of it, the Alliance still face 10 to 23 square (76 bits) possibilities to solve a cipher-text, which means it was almost impossible for Alliance to solve cipher-text by enumeration method. In the end, Enigma was be cracked by Alliance because the mistake made by German operator and the capture of Enigma. Scientist believed that the crack of Enigma Machine helped Alliance won the WW2 2 years advanced. After the World War Two, with the development of computer, human began to try the more sophisticated method to protect information.