A digital certificate can contain all different types of information depending on the organization, which created the certificate. Some of this information is common and included with all certificates. Other types of information may be left out, when it is not needed or being used. For example, some organizations may set an expiration date for the certificate, while other organizations, may decide that their certificates should never expire.
Two Types of Keys Can Be Used with a Digital Certificate
A digital certificate is based on using two types of encryption keys called a private key and a public key. The certificate issuer often retains the certificate with the private key and places it in the appropriate location, like on a network server. Users, who need to access this network server, will need the certificate containing the correct public key. When they connect to the server, their public key is compared to the private key on the server. As long as they match, they are given access to the server.