The OpenSSL configuration provided as ressource can be used with OpenSSL to create a certificate request like so:
This request can be sent using a HTTP POST request as multipart form data (for example from a file upload form inside a web page):
The file reply.tsr contains the timestamp. Alternatively, this also works with a POST request containing the timestamp query in the body of said request having the correct mime-type:
The content of the timestamp (useful for ascertaining the time and date for example) can be displayed for example with the help of OpenSSL command line tools like so:
To verify the timestamp, OpenSSL can help too: