HP UX Security Products and Features Software [1], [2], [3], [4], RC2 or RC4, Figure 1-6Symmetric Key Algorithm, Authenticating a Digital Signature

Common Data Security Architecture (CDSA) White Paper

Cryptography Service Provider (CSP) API

Figure 1-6 Symmetric Key Algorithm

[1]
A:		RC2 or RC4
	symmetric key algorithm		symmetric key

[2]

A:

A's data	symmetric key	A's encrypted data	B
B
B's public key	symmetric key	encrypted symmetric key

[3]

B:

B

B's private key encrypted symmetric key symmetric key

[4]

B:

symmetric key A's encrypted data A's data

Authenticating a Digital Signature

When B receives the data, B can be certain only of having received it from someone who used B’s public key to encrypt it. If B wanted to authenticate the message (that is, make sure that it was A who sent it), B would have to authenticate a digital signature that A would send with A’s data. This is shown in Figure 1-7, “Authenticating a Digital Signature.”

[1] Before encrypting data with a symmetric key algorithm, A hashes the data. This creates a

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