A PBX system handles routing of multiple phone calls with business-class services: direct-dial extensions, conference-calling, auto-answering with multiple options and ring groups. An IP PBX system offers the same services -- or more services. But instead of running everything through a computer box in your office, many IP PBX systems are hosted by the provider. With a hosted IP PBX solution, all you have to do is purchase the service, access it through your Internet connection, and then configure it yourself through the web. It's much easier and almost always much cheaper than PBX services using traditional landlines.