Private Key

In basic secret key cryptography, a private key is shared by the communicating parties. This enables each of them to encrypt and decrypt messages. There is great risk in this system - if the key is stolen or either party happens to lose it, the system can be penetrated by intruders. A more secure alternative to this system combines a public key with a private key, a protocol known as the PKI (Public-Key Infrastructure). A private key is protected in two ways: it can be stored on the hard drive of a computer, allowing a user to configured access, or it can also be stored in a web browser such as Internet Explorer and protected by a password. A third-party source can only use a private key with access to the file in which it is stored or knowing the password. Some programs allow a user to choose whether or not a password should be used to protect a private key. Not using a password is an option more suitable for someone who doesn’t share a computer with other users.