Public key infrastructure or PKI is a type of cryptography used to protect data and information in public domains where there is little or no security. For example, the Internet is a public domain which is open for everyone. Most people can access all different types of websites, data and information. Unless you use some type of security, like requiring a user name, password and a second form of authentication, anyone can access your website and date contained online.
Accessing Your Banking Information Online Uses PKI
When you access your banking information over the Internet, you are using PKI. This type of cryptography requires that you provide a user name and password to log into your banking information. Some banks even require a second form of authentication, which they accomplish by installing a certificate on your computer. You may notice that you can access your online bank accounts from your home computer. However, you get a message from another computer saying access was denied. This is because the other computer does not have the required certificate.