Abstract: Methods, signals, devices, and systems are provided for secure access to a network from an external client. Requests for access to confidential data may be redirected from a target server to a border server, after which a secure sockets layer connection between the border server and the external client carries user authentication information. After the user is authenticated to the network, requests may be redirected back to the original target server. Web pages sent from the target server to the external client are scanned for non-secure URLs such as those containing "http://" and modified to make them secure. The target server and the border server utilize various combinations of secure and non-secure caches. Although tunneling may be used, the extensive configuration management burdens imposed by virtual private networks are not required.

Abstract: A system and method for regulating access to a proxy cache server residing on an institutional intranet or local network provides a directory for storing user names that are appended to client requests for remote web site information. The proxy cache server reads the appended requests and either accepts or denies access to the requested information based upon predetermined access control guidelines relative to the specific user name. The access control guidelines can be stored on the directory, and down-loaded to the proxy cache server's memory as needed. The proxy cache server stores and retrieves requested site information via the Internet, but only retrieves and delivers requested site information to clients if authorization is approved.

Abstract: An air-fuel ratio controller adjusts the pressure of gaseous hydrocarbon fuel delivered to an internal combustion engine in order to minimize the emission of undesirable gases, specifically carbon monoxide and oxides of nitrogen. The controller includes a zirconium oxide sensor exposed to the engine exhaust gases, a thermocouple temperature sensor, an electronic signal conditioner which provides a linearized ramp signal, adjustable threshold trigger circuits which fire relays at specific ramp signal values and provide fail-safe operation, electropneumatic valves which respond to the relays and provide a fluid control signal, suitable adjustable flow restrictions and a gas pressure regulator which responds to the fluid control signal and regulates the pressure and thus the flow of gas to the internal combustion engine.