HSTS
HSTS (HTTP Strict Transport Security) is a response header that tells browsers to only ever connect to a site over HTTPS, never plain HTTP.
HSTS prevents downgrade and cookie-hijacking attacks by removing the insecure HTTP option entirely. Monitoring that the header is present (and that HTTP correctly redirects to HTTPS) protects users and SEO.
Related terms
SSL/TLS CertificateAn SSL/TLS certificate is a digital credential that enables encrypted HTTPS connections and proves a site owns its domain.TLS HandshakeThe TLS handshake is the negotiation at the start of an HTTPS connection where client and server agree on encryption and the server proves its identity with a certificate.HTTP Status CodeAn HTTP status code is a three-digit number a server returns to indicate the outcome of a request, such as 200 (OK), 404 (Not Found), or 500 (Server Error).
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