Smartcard Firewalls Revisited

Smartcards are being used as secure endpoints in computer transactions. Recently, the connectivity of smartcards has increased and future smartcards will be able to communicate over the TCP/IP protocol. In this work, we explore options for using a smartcard as an active node in a communication network rather than as an endpoint. We envision in particular a proxy firewall running on a smartcard and combining the best of both worlds: the smartcard as a secure environment, and the proxy firewall for securing the network. Facilitating the various security options smartcards offer, we show how to design a secure network firewall on a smartcard. We illustrate the usefulness of such a device in several scenarios.