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Lesson 6 Encrypting - Decrypting Data
Objective Types and uses of encryption

Types and uses of Encryption

Encrypting and decrypting data is nothing more than passing the data through an algorithm[1] to make something readable only to the intended recipients. The process for encryption is essentially identical to the process for decryption. At the document level, encryption takes an easily read plaintext[2] file and turns it into ciphertext using a key in conjunction with a specific algorithm. Encryption has become important not only in regard to e-mail, but also for network communications.
  1. Key: A method of opening an encryption. A key can be as simple as a string of text characters, or a series of hexadecimal digits.
  2. Ciphertext : Text which has been encrypted by some encryption system.

Encryption strength

Encryption strength is based on three primary factors:
  1. The first is strength of the algorithm
  2. The second factor is the secrecy of the key
  3. Length of the key

Strong encryption

The U.S. government classifies encryption that uses keys in excess of 40 bits as "strong encryption." U.S. companies wishing to export products that use strong encryption must first obtain State Department permission to do so. Although 40-bit keys are not always strong enough for financial transactions, they are usually sufficient for individuals' needs.

Encryption types

All types of encryption are subject to defeat. C View the Iimage below to see encryption types, descriptions and commonly used algorithms.

The diagram above describes the types of encryption.

Encryption threats

Symmetric, or single-key, encryption is a simple process that is fast and strong. However, all parties must know and trust each other completely, and have confidential copies of the key. Hackers can compromise symmetric keys either with a dictionary program , password sniffing, or by simply snooping through a desk, purse, or briefcase. One countermeasure is to change your key regularly. This can reduce the danger of having a symmetric key compromised.
  1. Dictionary program: A program specifically written to break into a password-protected system. A dictionary program has a relatively large list of common password names that the program repeatedly uses to gain access .
  2. Password sniffing: Finding a way to intercept the transmission of a password during the authentication process. A sniffer is a program used to intercept passwords.
  3. Key: A method of opening an encryption. A key can be as simple as a string of text characters, or a series of hexadecimal digits.

Click the link to read about encryption terms and their descriptions.
Encryption Methods

[1] Algorithm: A computable set of steps to achieve a desired result.
[2] Plaintext: A message before encryption or after decryption, i.e. in its usual form which anyone can read, as opposed to its encrypted form, ciphertext.