openwifiappliance

Software for wifi appliances built from the cheapest ali-express gray-market goods and the least amount of software.

Hardware Platform

"Converse":

• raspberry pi 3
• usb powerbank
• 4 port usb hub
• 3x usb wifi adapters
• u-blox 7; gps
• GEMBIRD card-reader
• xGB sd card for data (nilfs2 suggested)
• 2GB microsd for OS image

Power draw: 5.8W (~1.3A). Potential for brownout if hub uses power over rpi.

Tested wifi:

• ar9271; 802.11n (best)
• rt3572; 802.11ac (ok)
• rt5370; (ok)
• mt7601u; 802.11n (ok; hangs if too many adapters)
• rt3070; 802.11n (poor)

Building requirements

This should build wherever if you have docker on an otherwise reasonable linux system:

• make
• rsync
• docker

Installing the OS image

OWA_DEV=/dev/sdx make install-image

Data card

The system needs a flash card in addition to the system card. All scan data is written to the data card.

Each boot initializes a new data directory on the data card, /owa/<boot-time>, with the following directories:

• / -- tcpdump logs for device, iwconfig data, lsusb data
• gps/ -- gps logs, lsusb data
• log/ -- system logs