H3C Technologies H3C WX3000E Series Wireless Switches - Manual (Page 331)

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Configuring SSL
Overview
Secure Sockets Layer (SSL) is a security protocol that provides secure connection services for TCP-based
application layer protocols such as HTTP. It is widely used in e-business and online bank fields to ensure
secure data transmission over the Internet.
SSL security mechanism
Secure connections provided by SSL have these features:
• Confidentiality—SSL uses a symmetric encryption algorithm to encrypt data and uses the
asymmetric key algorithm of Rivest, Shamir, and Adelman (RSA) to encrypt the key to be used by the
symmetric encryption algorithm.
• Authentication—SSL supports certificate-based identity authentication of the server and client by
using the digital signatures. The SSL server and client obtain certificates from a certificate authority
(CA) through the Public Key Infrastructure (PKI).
• Reliability—SSL uses the key-based message authentication code (MAC) to verify message integrity.
A MAC algorithm transforms a message of any length to a fixed-length message.
Figure 137
illustrates how SSL uses a MAC algorithm to verify message integrity. With the key, the sender uses
the MAC algorithm to compute the MAC value of a message. Then, the sender suffixes the MAC
value to the message and sends the result to the receiver. The receiver uses the same key and MAC
algorithm to compute the MAC value of the received message, and compares the locally computed
MAC value with that received. If the two match, the receiver considers the message intact; otherwise,
the receiver considers that the message has been tampered with in transit and discards the
message.
Figure 137 Message integrity verification by a MAC algorithm
NOTE:
•
For more information about symmetric key algorithms, asymmetric key algorithm RSA and digital
signature, see "Managing public keys."
• For more information about PKI, certificate, and CA, see "Configuring PKI."