internet.nl checks websites and email server for their use of modern Internet standards such as HTTPS, DANE, HSTS, DMARC, etc.
Recently, a check for security.txt according to RFC9116 was added. The idea is to make it easier to report
security vulnerabilities. Previously, RFC2142 (section 4)
suggested the use of
Another check is for RPKI (Resource Public Key Infrastructure), aiming to make Internet routnig more secure. It is moreless directed at ISPs operating for securing BGP.