Node instance can be started on any host running a suitable
daemon. A master server process records the pool of slave daemons
currently running. When a new daemon is started, it registers with
this central server. Clients may request a list of hosts running
daemons from the main server, then ask for a particular Java object file
to be run on any subset of those hosts. Typically the client is an
applet running in a browser, and the main HPJ server runs on the same
host as an HTTP server from which the applet was downloaded.