Determining the Difference between Public and Private Certificates

As mentioned in the previous section, public certificates are used to secure websites and other publicly accessible web applications. They are issued by a CA and trusted by all major web browsers. They validate the website’s identity to visitors and ensure encrypted communication; this is commonly indicated by the padlock icon in web browsers next to the URL address. Public certificates can be obtained from various sources, including ACM and commercial CAs. ACM allows AWS customers to request and manage public certificates easily and for free.

Private certificates secure private networks and applications such as internal websites, VPNs, APIs, internal servers, IoT devices, and other sensitive resources. As mentioned earlier, they are issued by a private CA and trusted only by devices and applications configured to trust that CA. They authenticate and encrypt data traffic between these resources, enhancing...