What is TLS-RPT?

TLS-RPT (Transport Layer Security-Reporting and Performance) is a standard for reporting security and performance information about a website's certificate and the connection to the website. It helps to identify misconfigurations or other issues that might affect the security or performance of a website, and allows website operators to take corrective action. In particular, it helps to identify and prevent certificate misissuance, which can be a security vulnerability.

TLS-RPT (Transport Layer Security-Reporting and Performance) works by providing a way for website operators to collect and report information about their website's certificate and the connection to the website. This information is collected by a client (such as a browser) when a user visits the website, and is then sent to a reporting server designated by the website operator. The reporting server can then analyze the information and provide feedback to the website operator about any potential issues or misconfigurations.

The specific details of how the information is collected and reported can vary depending on the implementation, but the standard defines a set of required and optional fields that should be included in the report. These fields include information such as the certificate chain, the cipher suite used for the connection, and the server's response to certain requests.

The website operator can then use this information to identify and fix any issues that might be affecting the security or performance of their website. For example, if the report indicates that the certificate chain is not complete or that the server is not configured properly, the operator can take steps to correct the problem.

TLS-RPT also allows for the collection of performance data, such as the time it takes for a server to respond to a request, which can help website operators optimize their website's performance.