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Showing posts from August, 2016

TOWL - Telemetry over Opportunistic WiFi Links

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Premise & Background: Can you build a "LoJack" style asset tracking capability using open WiFi hotspots? The proliferation of cheap, lightweight WiFi embedded ("IoT") devices made me wonder.  The WiFi association stack, DHCP client stack, et al. has to be incredibly lightweight and simple to fit in the firmware on, say, an ESP8266.  If you programmed one to scan, find an AP, associate, get an address, and send a single packet - would it be able to do it fast enough to report its location from a moving vehicle? [Aside: This is actually something I've wondered about for years, but the IoT chips offered a unique and low-cost way to try it.] "But wait," you say, "there really aren't that many open APs these days.  Most of them are captive or paywall portals, or at least make you agree to some goofy ToS." Right, but as has been pointed out multiple times by multiple people all the way back to Dan Kaminsky's DNS tunneling ta...