Click: on the options graphic below to discover it's uses.
Port and Address
These are the standard bits of data required to expose the Phone Server services to the outside world. The address is one of the addresses of your network cards, and the port is the section of the TCP stack the application reads from and writes to. The port can be any number (< 65,000) as long as it's not used by another service on your computer. If you move to a different port you will have to inform all the users (and remember this yourself) since the default of the NetCaller is to use 5502, expecting to find the server there. If you are running a firewall you will have to open the port on it. You may also need to read about firewalls
Bind To Domain
If you have a static IP or use a service such as no-ip because your ISP changes your address frequently, you can also have the server bind to the DNS name. Of course the name must be bound to the host PC.
Show Connections
It can be a little disturbing if a connection window appears while you're gaming or surfing. If this is checked, all connection windows will be hidden if the server is running in the system tray.
Phone Number
This is the phone number of the remoted phone so that connected clients know what number they are dialing from or what number to report as a phone number.
City of Origin
This is displayed when people connect to this Phone Server. Together they look like this on the remote NetCaller.
Phone Server will automatically check for new versions once a week if you want. This way you will always be aware of bug fixes and feature improvements.