A system for process control comprises a server digital data processor and
a client digital data processor that are coupled by a network, such as
the Internet or an Intranet. The server digital data processor, which is
additionally coupled to a control/sensing device and any associated
interface equipment (collectively, referred to as "process control
apparatus"), includes a command processor that transfers information
between the network and the process control apparatus. The client digital
data processor includes an information client (e.g., a so-called Internet
web browser) capable of requesting and receiving an applet from the
server digital data processor. The information client, further, defines a
hardware-independent and operating system-independent virtual machine
environment within the client digital data processor. The client digital
data processor executes, within that virtual machine environment, an
applet for configuring the client digital data processor as a "process
controller" that establishes communications over the network with the
command processor and that monitors and/or controls the process control
apparatus via those communications.