Julius Caesar employed a rotating cylinder to form a simple substitution cipher. 12Įncryption has existed for thousands of years. 11 In 2010, the method was purchased by Symantec Corp. 10 A popular asymmetric encryption methodology is Pretty Good Privacy (“PGP”) which Phil Zimmermann created in 1991. 9 Diffie and Hellman first developed asymmetric keys in 1976. It is available for everyone to use, whereas the key applied to decrypt information is called a private key, and only specific individuals possess this key. 8 The key used to encrypt data is a public key. 7 When an encryption key is asymmetric, one key is used to encode information, and another key is employed to decode data. 6 When an encryption key is symmetric, the same key is used to encrypt and decrypt data. 5Įncryption keys can either be symmetric or asymmetric. 4 Although it is logically possible to decrypt data without a key, it requires considerable technical skill that is usually beyond most people’s grasp. 3 Typically, an encryption scheme employs a pseudo-random encryption key that is created by a pre-specified algorithm. 2 With encryption, data is encrypted using a cipher. 1 Encryption does not prevent an individual from accessing data, but it does stop persons from getting the data’s content. In cryptography, encryption is a mechanism whereby a message or information is encoded to access the data, and unauthorized parties cannot obtain the data.

How to encode backdoor in pdf for mac