In order to use ShelfServer, you must have the following:
A JRE or JDK is sufficient to run ShelfServer. The installer package may have automatically installed a JRE on Windows.
Accessing ShelfServer across network segments is possible provided ShelfServer's TCP port is forwarded between the segments, but Bonjour-based autodetection will not function. Manually entering the ShelfServer's address (as seen from the iPhone's network segment) will allow ShelfServer to function. Official support for this mode of operation is limited due to the vast number of potential configurations, but it's known to work so long as the network is properly configured.
Accessing ShelfServer across the the Internet is possible so long as your external router is configured to forward ShelfServer's TCP port to your computer. Use of a strong password is highly recommended. Support for this configuration is very limited, and no warranty is made as to the security of ShelfServer in this configuration. Every effort is made to ensure that ShelfServer is a secure product, but the developers accept no responsibility for ShelfServer's exposed to the public Internet. Security patches and vulnerability notifications are of course welcome.