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VPN
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 for confidentiality.
Secure email
Emails require confidentiality, integrity, authentication, and non-repudiation. PKI can address these
needs. The secure email protocol that is developing rapidly is 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 an 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 of the communication parties can verify each other's identity through digital
certificates.
Operation
In a PKI-enabled network, an entity can request a local certificate from the CA, and the router can check
the validity of certificates. Here is how it works:
1.
An entity submits a certificate request to the RA.
2.
The RA reviews the identity of the entity and then sends the identity information and the public key
with a digital signature to the CA.
3.
The CA verifies the digital signature, approves the application, and issues a certificate.
4.
The RA receives the certificate from the CA, sends it to the LDAP server to provide directory
navigation service, and notifies the entity that the certificate is successfully issued.
5.
The entity retrieves the certificate. With the certificate, the entity can communicate with other entities
safely through encryption and digital signature.
6.
The entity makes a request to the CA when it needs to revoke its certificate. The CA approves the
request, updates the CRLs, and publishes the CRLs on the LDAP server.
Configuration task list
Task Remarks
Required
Required
Submitting a PKI certificate request
Submitting a certificate request
in auto mode
Required
Use either approach
Submitting a certificate request
in manual mode
Retrieving a certificate manually
Optional
Configuring PKI certificate verification
Optional
Destroying a local RSA or DSA key pair
Optional
Optional
