Understanding Cryptography

In this section:

• About Encryption
• Advanced Encryption Standard
• RSA Encryption

Cryptography is a field of mathematics concerned with the study of algorithms for encrypting and decrypting data.

Encryption transforms a plain text message using an algorithm, or cipher, into a coded message called ciphertext. Only designated users possessing special knowledge, usually referred to as a key, can access the data.

Cryptography involves two processes:

• Encryption
• Decryption

Encryption can be used to protect computer data, such as files on computers and removable storage devices. The purpose of encryption is to prevent third parties from accessing the sensitive information. This is particularly important for sensitive data. Encrypting such data helps protect it, should physical security measures fail.

Decryption is the process of decoding data that is encrypted using a secret key or password. If the password is not correct, it will be impossible to get the encryption key and subsequently decrypt the encoded information.