HP 5120 SI Series

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Public key configuration
This chapter includes these sections:
• Asymmetric key algorithm overview
• FIPS compliance
• Configuring the local asymmetric key pair
• Configuring a remote host's public key
• Displaying and maintaining public keys
• Public key configuration examples
Asymmetric key algorithm overview
Basic concepts
• Algorithm—A set of transformation rules for encryption and decryption.
• Plain text—Information without being encrypted.
• Ciphertext—Encrypted information.
• Key—A string of characters that controls the transformation between plain text and ciphertext. It is
used in both the encryption and decryption.
Key algorithm types
As shown in Figure 78, the information in plain text is encrypted by an algorithm with the help of a key
before being sent. The resulting ciphertext is transmitted across the network to the receiver, where it is
decrypted by the same algorithm also with the help of a key to obtain the original plain text.
Figure 73 Encryption and decryption
The following types of key algorithms are available, based on whether the keys for encryption and
decryption are the same:
• Symmetric key algorithm—The keys for encryption and decryption are the same. Commonly used
symmetric key algorithms include Advanced Encryption Standard (AES) and Data Encryption
Standard (DES).
• Asymmetric key algorithm—The keys for encryption and decryption are different, one is the public
key, and the other is the private key. The information encrypted with the public key can only be
decrypted with the corresponding private key, and vice versa. The private key is kept secret, and the
public key may be distributed widely. The private key cannot be practically derived from the public
key.