WMBE Raspberry Pi mobile router

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Wikimedia Belgium owns a WMBE Raspberry Pi mobile router since August 2017. This SoC appliance (the black box) can be used as a mobile Wi-Fi accesss point to e.g. give Wikipedia training on remote locations that do not have a fixed internet connection. It can be used for other occasions as well: conferences, board meetings, hackathons, edit-a-thons and other activities.

Because mobile roaming (billing) in Europe has been revoked in the summer of 2017 (thank you EU), we can use the device in any European country. We can use up to 5 GB data per month.

Contacts[edit]

Functionality[edit]

  • Mobile router (meaning you can use it anywhere)
  • Hardware: Raspberry Pi
  • Linux (Raspbian)
  • Firewall
  • Can be powered from mains, or from USB battery
  • (built in) Wi-Fi access point
  • Internet connection (plug-and-play) - either:
    • Mobile 4G/3G data connection (USB data stick)
    • Ethernet LAN connection
    • USB thetering
Optional
  • Local MediaWiki server

Components[edit]

Mobile router and Wi-Fi access point components
Subsystem Component Description
Main system Raspberry Pi 3 Built-in Wi-Fi access point1,2
Micro-USB power supply3 Main(s) power, USB battery
USB 4G data stick4 Mobile internet, with data subscription
Alternative power supply5 Micro-USB cable Power from laptop
USB console cable (serial) System console via PuTTY or screen for system maintenance/troubleshooting
Optional GUI Mini keyboard and mouse pad6 Console or X Windows
Mini-USB cable Charge keyboard battery
HDMI cable 5 m to connect a flat screen or an external projector
Optional fixed network Ethernet cable7 5 m to connect a laptop, or switch
Network switch Network ethernet hub
Ethernet cable One for each client
Optional mobile network Smartphone, micro-USB cable Mobile USB tethering8
Notes
  1. A 2,4 GHz Wi-Fi network has a limited speed of only 15-20-40 Mbits/s depending on the interference
  2. It is currently using channel 6+11 (could be changed to 1+6) with a bandwidth of 2×20 MHz
  3. Could be replaced by 2 USB power cables connected to a laptop (alternative power supply)
  4. The mobile 4G data stick has a speed of 15 Mbit/s (under good network conditions)
  5. One laptop USB port can only sustain 100 mA. Therefore you need 2 ports to power the Raspberry Pi
  6. You could connect a normal keyboard and mouse as well
  7. The fixed ethernet speed is 100 Mbit/s (internal USB 2 interface)
  8. Speed can be much higher, but you should use a mobile data bundle

How to use[edit]

  • Step 1: take the Raspberry Pi and connect it to the power supply:
    • Option 1: connect external power supply, or
    • Option 2: connect two USB cables with laptop (connect black first, blue as second)
  • Step 2: Plug in the mobile USB stick in the Raspberry Pi

System should be ready within 1 minute. When ready the led-light on the mobile stick should be ON (and no longer flashing).

  • Step 3: Connect your laptop(s) with the Wi-Fi network WMBEGVP

Shutdown[edit]

  • First: Remove the mobile USB stick
  • Second: Remove the power cable(s)

Technical details[edit]

Mobile status LEDS[edit]

Data stick status
LED Status
Off (power) Off
Flashing Connecting
On Connected
Network status
LED color Status Speed
Green 2G
Blue 3G
Cyan 4G 10-15 Mbit/s

Power supplies[edit]

  • Connect the external USB power supply adaptor to mains (simplest solution)
  • Or connect the USB power cable and USB console cable to a laptop (run on battery) ⇒ you are completely mobile!
  • You should power your laptop from mains, if possible, to have a longer duration

Wi-Fi access point[edit]

  • SSID: WMBEGVP

When to use[edit]

You are on a location where there is no internet. You want to provide internet to multiple devices via Wi-Fi. Examples:

Caveat[edit]

  • Do not use it in non-EU countries like Norway, Switserland (huge roaming cost)
  • The appliance contains a built-in DHCP server. Do not connect the LAN port to another network; it will disturb the other network.
  • The LED light should stay ON; if not there is either a network problem, a power supply, or a SIM card problem

Troubleshooting[edit]

Verify the 4G data stick on Windows=[edit]

  • Connect the data stick to a Windows lapop
  • Goto Windows Explorer
  • Click on setup.exe
  • Configure the device
  • Click on connect

Now you can remove the data stick and connect it again to the Raspberry Pi

System check and setup[edit]

Via SSH[edit]

ssh pi@192.168.40.1

On Linux[edit]

  • Connect the USB console cable
  • Verify the USB device
ls /dev/ttyUSB?

Output:

/dev/ttyUSB0

or

/dev/ttyUSB1
screen /dev/ttyUSB0 115200

or

screen /dev/ttyUSB1 38400

Now you can login and verify or configure the device.

To close the session: Ctrl-a k y

Invoicing[edit]

The hardware costs 227 euro (including 80 euro for the USB 4G data stick). The monthly mobile subscription is 15 euro for 5 GB. Out-of-bundle traffic costs 50 euro / GB! Roaming is 10000 euro / GB... Luckily EU-countries are no longer applying roaming tariff.

  • You can verify the data usage online
  • When the bundle forfait is reached we get an e-mail

A typical edit-a-thon can easily use 1 GB... A monthly invoice has to be settled.