DNSSEC is used to sign the DNS zone of your domain (s). This ensures that only name servers respond to DNS queries that are authorized to do so. Attacks that try to intercept or change DNS queries become more difficult.
With INWX, we offer you the option to have your domain fully automatically signed with the DNS zone for your domain (s). You can not store your own keys in this mode. If you run your own (or an external) name server, you can continue to store your own keys in manual mode.