A Crestron controller connects to a HAL or PC running Halogen via TCP/IP. The easiest way to accomplish this connectivity is by assigning the HAL or PC a static IP address.
You configure a HAL’s static IP addresses from the Host Device Settings dialog in the Hardware workspace. To access this dialog, connect to your HAL, hover your mouse over the HAL bar at the top of the Hardware Map, then click on the gear icon that appears. The Host Device Settings dialog is only available when Halogen is connected to a HAL. Host Device Settings like static IP assignments reside solely on that HAL and do not travel with the Halogen configuration file.
PCs are frequently setup to use dynamic IPs but a static IP is preferable if you want to use your PC in place of a HAL during development. The controller tries to connect to a TCP server (your PC in this case) at a specific IP address. If your PC has a dynamic IP address assigned to it that address may change if it is disconnected from the network or the DHCP lease expires. You also probably do not want to configure your PC with the same static IP as your HAL in the event that both are connected to the same network.
Control system networks are typically private networks with no direct route to the Internet except through a gateway or proxy server. Certain IP address ranges are reserved for private networks. 10.0.0.0 to 10.255.255.255 is one of those address ranges. Start with a small self-contained network. Plug your Halogen PC, controller, XPanel PC and HAL into the same Ethernet switch and assign each one a unique static IP in the 10.0.0.0 network.