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Certificate management 
PKI overview 
The Public Key Infrastructure (PKI) is a general security infrastructure for providing information security 
through public key technologies, and it is the most widely applied encryption mechanism currently. 
H3C's PKI system provides certificate management for IP Security (IPsec), Secure Sockets Layer (SSL), and 
WLAN Authentication and Privacy Infrastructure (WAPI). 
PKI, also called asymmetric key infrastructure, uses a key pair to encrypt and decrypt data. The key pair 
consists of a private key and a public key. The private key must be kept secret but the public key needs 
to be distributed. Data encrypted by one of the two keys can only be decrypted by the other. 
A key problem of PKI is how to manage the public keys. Currently, PKI employs the digital certificate 
mechanism to solve this problem. The digital certificate mechanism binds public keys to their owners, 
helping distribute public keys in large networks securely.  
With digital certificates, the PKI system provides network communication and e-commerce with security 
services such as user authentication, data non-repudiation, data confidentiality, and data integrity. 
The PKI technology can satisfy the security requirements of online transactions. As an infrastructure, PKI 
has a wide range of applications. Here are some application examples: 
•  VPN—A virtual private network (VPN) is a private data communication network built on the public 
communication infrastructure. A VPN can leverage network layer security protocols (for instance, 
IPsec) in conjunction with PKI-based encryption and digital signature technologies to achieve 
confidentiality. 
•  Secure email—Emails require confidentiality, integrity, authentication, and non-repudiation. PKI 
can address these needs. The secure email protocol that is currently developing rapidly is 
Secure/Multipurpose Internet Mail Extensions (S/MIME), which is based on PKI and allows for 
transfer of encrypted mails with signature. 
•  Web security—For Web security, two peers can establish a Secure Sockets Layer (SSL) connection 
first for transparent and secure communications at the application layer. With PKI, SSL enables 
encrypted communications between a browser and a server. Both the communication parties can 
verify the identity of each other through digital certificates. 
 
  NOTE: 
For more information about PKI, see 
H3C WA Series WLAN Access Points Security Configuration Guide
.
 
Configuring PKI 
The system supports the following PKI certificate request modes: 
•  Manual—In manual mode, you must retrieve a CA certificate, generate a local RSA key pair, and 
submit a local certificate request for an entity. 
•  Auto—In auto mode, an entity automatically requests a certificate through the Simple Certification 
Enrollment Protocol (SCEP) when it has no local certificate or the present certificate is about to 
expire.