Encryption Algorithms
There is a wide variety of encryption algorithms. System administrators looking to keep their data as secure as possible must choose from among these many algorithms, which include DES, Triple DES, TRIPLE_DES_3KEY, RC2, DESX, AES and a host of other options.
Each of these encryption algorithms will have its own strengths and weaknesses, but there are some general guidelines that people can follow when trying to choose a type of encryption. In general, really strong encryption methods will ask more of a computer than weaker methods. Another general observation is that long keys are preferable to short ones. Long keys are harder to crack than short keys, which can be guessed more easily.
Two main types of encryption are symmetrical and asymmetrical encryption. Asymmetric encryption tends to be stronger than symmetric encryption, if the person is using the same key length for both. However, this stronger encryption will also ask more of the computer, and will therefore be slower.
Sometimes, combining the two encryption types can be useful. If there is a lot of data to encrypt, a symmetric key is better. The symmetric key can then be further encrypted with an asymmetric key. This allows the asymmetric key to be applied to a larger amount of data than it would normally be able to be applied to efficiently.
The elements used to produce keys are called ciphers. There are two types of ciphers used for encryption: bock ciphers and stream ciphers. In general, block ciphers with long keys will tend to be more secure than stream ciphers, just as long, complex passwords are more secure than short passwords.