Cryptography

References

http://www.garykessler.net/library/crypto.html

Cryptography

http://cacr.uwaterloo.ca/hac/

http://www.rsa.com/rsalabs/node.asp?id=2176

https://www.cryptochallenge.com/home/history

Cryptography - Outlook

Cryptography - Fun Facts

The future of cryptography is quite bright. Securing and encrypting data will always be important in this modern era.

We see developments in almost every aspect of our lives in terms of securing data. Almost everyone now has "chips" in their debit cards. This just an example of how current cryptography is.

Cryptography is going to play huge rolls in other upcoming computer science developments. With quantum computing around the corner, cracking algorithms will be easier and we'll have new cryptography challenges to overcome.

• Alan Turing (father of computer science and artificial intelligence) was one of the lead cryptanalysts during WWII. He brought formality to computer algorithms and applied his work to breaking the German cryptographic algorithms for the British.

• Computers use bits instead of letters when encrypting, this trips up some of the everyday "hackers" who think with letters.

• In history cryptography has probably been used by lovers just as much as by military leaders or diplomats. It seems that everyone has a secret message to send!

• RSA encryption algorithms use prime numbers that must be kept secret for the encryption!

I can't imagine a world without passwords,

or banking but I can imagine a world with Cryptography.

Cryptography - Timeline

Cryptography - Introduction

The field of cryptography has grown by leaps and bounds. With the help of computers, we can develop more complex algorithms to encrypt information.

One key development in the field was the use of Public-key Cryptography. In 1976 Whitfield Diffie and Martin Hellman developed the use of both a private key and a public key. Both keys are related mathematically and are used in the process of cryptography. The private key is used by the sender to encrypt the data, and the public key decrypts it. The first practical system was developed in 1978.

Another development has been the "Hash Function". Most often this function produces ciphertext that can not be decrypted. The plaintext is irreversibly changed. This is used primarily for passwords. Although you can't decrypt the password, you can put the input through the function and then check if it matches the password.

Commonly, the term "code" is used to denote secret messages. With games based around cracking the "code", or guessing the secret message. Cryptology is essentially all about the privacy or confidentiality of a secret "code".

Hash functions can also force the input to be

encrypted into cipher text of a specified length.

Cryptography - Timeline

Cryptography - Info

Cryptography takes the sender's message (or plaintext) and encrypts it with a specific key. This code (or ciphertext) can then be decrypted by the receiver. This results in the original message (or plaintext).

Cryptography - Introduction

In modern times, it is coupled with mathematical algorithms and techniques to provide anonymity for computer users and is a major source of security for individuals.

This is one example of how cryptography works. But the main idea is to encrypt the data, and decrypt the data.

Before the modern era of computers, cryptography was mainly used to encrypt messages. This was used by great leaders like Caesar as well as many other diplomats. They would use algorithms/devices called "ciphers" to encrypt their message.

Cryptography is the practice of securing communication in the presence of a third party. It is used to encrypt and secure information from a sender and decrypt it for the receiver.

Cryptography - Info

Cryptography is an issue for many people. On one hand computer scientists want to be able to encrypt their vital data, but hiding information from the government can have serious legal implications.

There have even been prohibitions on the use of cryptography. The government of China requires a license before the use of it.

This is key in the computer science field because it is used so globally. It is used by ATMs, password handlers, disk encryption,

and electronic banking.

The Caesar Cipher is a simple algorithm

that shifts the message's letter a

predetermined distance in the alphabet.

E is shifted 3 to the left so as to output B

in a Caesar's Cipher.

Cryptanalysis is the study and science of breaking down these secret codes.

Cryptanalysts focus on finding the encryption key which is done using algorithms and then by working backwards. Sometimes they just guess the meaning of certain symbols/letters.

"Hackers" are often the people we think of when it comes to these kinds of activities. However, there is both a professional and recreation sector for cryptanalysis. Users of Reddit have created a community for code-breaking.