HP A5830 Series, Руководство по настройке

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Configuring public keys
To protect data confidentiality during transmission, the data sender uses an algorithm and a key to
encrypt the plain text data before sending the data out. The receiver uses the same algorithm with the
help of a key to decrypt the data, as shown in
Figure 42 .
Figure 42 Encryption and decryption
The keys that participate in the conversion between the plain text and the cipher text can be the same or
different, dividing the encryption and decryption algorithms into the following types:
•
Symmetric key algorithm —The keys for encryption and decryption are the same.
•
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. Asymmetric key algorithms include RSA and DSA.
Asymmetric key algorithms are widely used in various applications. For example, SSH, SSL, and PKI use
the algorithms for digital signature. For information about SSH, SSL, and PKI, see " Configuring
SSH2.0 ," " Configuring SSL ," and " Configuring PKI ."
Asymmetric key algorithms can be used in two scenarios for two purposes:
•
To encrypt and decrypt data —The sender uses the public key of the intended receiver to encrypt the
information to be sent. Only the intended receiver, the holder of the paired private key, can decrypt
the information. This mechanism ensures confidentiality. Only RSA can be used for data encryption
and decryption.
•
To authenticate a sender —Also called "digital signature." The sender "signs" the information to be
sent by encrypting the information with its own private key. A receiver decrypts the information with
the sender's public key and, based on whether the information can be decrypted, determines the
authenticity of the information. RSA and DSA can be used for digital signature.
Public key configuration task list
The configuration tasks enable you to manage the local asymmetric key pairs and configure the peer
host public keys on the local device. By completing these tasks, your host is ready to work with
applications such as SSH and SSL to implement data encryption/decryption, or digital signature.
Complete these tasks to configure public keys:
Task Remarks
Configuring a local
Creating a local asymmetric key pair Required