    dnssec-policy string {
        dnskey-ttl duration;
        keys { ( csk | ksk | zsk ) key-directory lifetime duration algorithm integer [ integer ] ; ... };
        parent-ds-ttl duration;
        parent-propagation-delay duration;
        parent-registration-delay duration;
        publish-safety duration;
        retire-safety duration;
        signatures-refresh duration;
        signatures-validity duration;
        signatures-validity-dnskey duration;
        zone-max-ttl duration;
        zone-propagation-delay duration;
    };