A technique for the delivering a client-based firewall. A firewall security device is configured for connecting to individual clients, e.g., personal computers, for providing firewall security measures directly to the client. The firewall security device is configured as a electronic dongle which is attached to an external communications port of the client, e.g., the parallel communications port. The incoming communications stream to the client from, e.g., public networks, is passed through the firewall security device. In this way, the firewall security device applies and delivers a set of standard network security measures thereby protecting the client from security breaches triggered by the communications stream received from the public network. Advantageously, the firewall is delivered directly by the client without intervention, use, or connection to a separate firewall server.