Overview
The Cradlepoint IBR900 Router is the heart of our computer network. The router creates and manages Molly’s network and interface to the Internet, both the wired and the wireless portions.
Wired Network
The router only has two ethernet ports, one for the WAN (wide Area Network) and one for the LAN (Local Area Network). So we added the COR Extensibility Dock, which provides two extra LAN ethernet ports. Fortunately we only needed 4 ethernet ports. All the major components of the system are connected via a wired ethernet network.
Physically, the network is wried up with Cat5 cables and RJ45 connectors as follows
- Router WAN <–> Starlink
- Router LAN <–> Mintbox
- Router Extensibility Dock LAN A <–> NAS
- Router Extensibility Dock LAN B <–> Raspberry Pi
Wireless Network
The Cradlepoint router also has five connections to antennas for the wireless network; two for wifi, two for cellular and one to receive GPS signals.
The Cradlepoint modem support MIMO (Multiple In, Multiple Out) antennas for wifi and cellular. MIMO provides increased capacity and higher signal reliability through multi path propagation. There is a single active GPS antenna connection. The antenna we use is the Proxicast 5-in-1 Professional Low-Profile MIMO antenna. This antenna is proving to be very reliable.
Physically the antenna connections are to coaxial cable with SMA connectors. It is important to use a high quality antenna, cable and connectors. Cellular and wifi use very high frequencies, so any issues in the cable or connectors will result in poor wireless performance. Even with high quality components, it is still a good idea to keep the cable runs as short as possible.
The router is located in the electrical cabinet which is electrically very noisy. To ensure this electrical noise does not impact the wireless network, our antenna is located away from the electrical cabinet on the other side of the truck.
Internet Access
There are three ways we can access the Internet from the Network. Each have their own advantages and dis-advantages.
Starlink. This Internet connection provides a high bandwidth, when it is connected. However, it is not always connected. We only setup the antenna when we are stopped and are in camp with a clear view of the sky. And when we leave camp, we disconnect and take down the Starlink antenna. Therefore we do not use Starlink while in motion. We are currently subscribed to the RV plan, which provides coverage for all of North America and we can stop and start the service as we wish.
When Starlink is setup, it works great with good Internet speeds and a mostly reliable connection. As mentioned above, it does not work while in-motion(1) or when the sky is obstructed, by either trees or buildings. So, it is limited in this sense.
Note (1): Starlink offers in-motion Internet, using a more powerful and larger antenna than the one we have and a more expensive service subscription. And while we would love to have in-motion Internet, the in-motion antenna consumes about twice the energy of the rectangular Gen 2 antenna we have. Additionally the in-motion antenna would need to be mounted on our roof so it can be used while driving, but this means it would likely be under trees while stopped and in camp. So, for the moment, we are staying with the rectangular Gen 2 antenna and RV subscription.
The rectangular antenna can be modified for in-motion use, but this modification is not likely allowed under Starlink’s Terms of Service.
Cellular. This Internet connection has the advantages that it is always on, at least while in cellular coverage. In North America, the cell network is well developed and we typically have service when on major roads. And typically no cell network when in the back-country. We have the Google Fi plan with unlimited for our iPhones, and this plan allows us to get a SIM which we have inserted into the Cradlepoint modem. The Google Fi network is not as good as other networks like at&t and Verizon, but it is good enough.
Wifi as WAN. This last Internet connection we do not use very often. The main purpose of the Cradlepoint modem is to create a wifi network as part of our Local Area Network. But the modem can also be configured to connect to an outside wifi network that has access to the Internet. This mode is called Wifi as WAN. It is quite useful if the camp ground offers Internet via wifi, and we haven’t setup Starlink, for whatever reason.
OBD-II Connection
The Cradlepoint router also has a serial connection to the OBD-II port on Molly, and is able to receive high-level diagnostic information from the FUSO Engine Control Unit (ECU). See Other Useful Links for more information
Other Useful Links
- Starlink Installation
- OBD-II Setup
- Electrical Wiring for Networking