As I describe in the book, a "minimal hassles" way to access a Web service running on an embedded computer behind a NAT or firewall is via a cloud-based relay.
My company Oberon microsystems developed such a relay called Yaler, which was spun off into a separate company. For details, please visit http://yaler.net/.
Even if you don't want to use a relay server, you can run my book examples that use the Gsiot.Server library within your local-area network, simply by deleting the RelayDomain and RelaySecretKey properties from the examples!