The invention describes a novel method for securing authentic client access to online confidential resources by means of a physical hard key/card device, which does not need a custom card reader, but uses the optical disc drive of any remote computer to conduct a highly secure online transaction on the Internet. Such real online card key (ROCK) device can be read by an optical disc drive of a computer, without allowing any of the file viewing, copying and editing functions. Such ROCK device can be used as a real world physical hard key for accessing secured networks and conducting secure online transactions. It can also be used as a fully functional versatile credit card with additional magnetic stripe and manual authentication methods available on the non-reflective surface of the optical disc based ROCK optical disc card of the present invention.