Does using Encryption slow things up?
Negligibly on any modern computer. The length of your passphrase is immaterial to the speed of decryption. But different encryption algorithms vary significantly. One of the fastest is Twofish and probably the slowest is 3DES (triple DES). This applies only to symmetrical encryption programs. PGP uses RSA or Diffie-Hellman generated keys, which in turn are used to encrypt/decrypt a randomly generated session key. The RSA key is very slow, but as it is only used to encrypt/decrypt the 128 bit CAST5 or IDEA session key its slowness is not noticed.
There is a small speed penalty because your computer has to encrypt to write to disk and decrypt to read from it. In practice on a modern machine, using the Blowfish (or Rijndael with BestCrypt) cipher, the encryption is totally transparent in normal use. 16. Do I need a PGP passphrase if I store my keyrings within my encrypted drive? It is good security practice to use a passphrase, but for level 3 security it is essential because level 3 security is intended to ensure your secret data are safe if attempts are made to hack into your computer whilst online or if your computer is compromized in your absence.
