To encrypt a file or other information stored in a computer means to convert it into a secret code so that it can't be used or understood until it is decoded or decrypted. You might want to encrypt a file if it contained a secret formula for a new invention, or some financial plans that your competitors would love to know about in advance. When you encrypt something, the computer will ask you to set up a password. After that, no one will be able to make sense of the information unless they have the same password.
Encryption hides your data from curious eyes. This is a process of encoding data to prevent unauthorized person from viewing or modifying it. The main features of data encryption are:
The process of data encryption consists of certain steps. The data passes through a mathematical formula called an algorithm, which converts it into encrypted data called ciphertext. These algorithms create a key and then encapsulate the message with this key.
There are two types of encryptions: asymmetric and symmetric.
In public key (asymmetric) encryption, two mathematically-related keys are used: one to encrypt the message and the other to decrypt it. These two keys combine to form a key pair. Asymmetric encryption provides both data encryption and validation of the communicating parties' identities and is considered more secure than symmetric encryption, but is computationally slower.
A public key encryption scheme has six major parts:
The asymmetric data encryption process has the following steps:
The asymmetric data decryption process has the following steps:
Private Key encryption (Symmetric), also referred to as conventional or single-key encryption is based on secret key that is shared by both communicating parties. It enquires all parties that are communicating to share a common key. The sending party uses the secret key as part of the mathematical operation to encrypt (or encipher) plain text to cipher text. The receiving party uses the same secret key to decrypt (or decipher) the cipher text to plain text.
Examples of symmetric encryption schemes are the RSA RC4 algorithm (which provides the basis for Microsoft Point-to-Point Encryption (MPPE), Data Encryption Standard (DES), the International Data Encryption Algorithm (IDEA), and the Skipjack encryption technology proposed by the United S12;tesgovernment (and implemented in the Clipper chip).
An encryption scheme has five major parts:
When using this form of encryption, it is essential that the sender and receiver have a way to exchange secret keys in a secure manner. If someone knows the secret key and can figure out the algorithm, communications will be insecure. There is also the need for a strong encryption algorithm. What this means is that if someone were to have a ciphertext and a corresponding plaintext message, they would be unable to determine the encryption algorithm. There are two methods of attacking conventional encryption - brute force and cryptanalysis. Brute force is just as it sounds; using a method (computer) to find all possible combinations and eventually determine the plaintext message. Cryptanalysis is a form of attack that attacks the characteristics of the algorithm to deduce a specific plaintext or the key used. One would then be able to figure out the plaintext for all past and future messages that continue to use this compromised setup.