IoT Devices and Public WiFi Networks

The "Internet of Things" is arriving more and more in our gadget-filled and technology-oriented lifestyle. Apple TV, gaming consoles, Amazon Echo (Dot / Tap) with Alexa and many other IoT devices require a wireless connection to the internet. But what about taking them on your travels? Sure, they are small, compact and easy to use – so you take them with you. But now what? Where do you get your WiFi from? The hotel's network requires you to sign in on a web page to verify that you are an active customer. Can't really do that with your IoT device, can you? In my case, I had to sign my newly acquired Amazon Echo Dot 2.0 onto the network. But it wouldn't let me do it – despite saying that the page to log in will be displayed when I push "continue". It never happened.

The Solution: MAC Address Spoofing

Then I had an idea. If my laptop's access is linked to its MAC address in the hotspot server's database this would mean that – if I could change my MAC address – I could sign on with the address of the Echo Dot and then the Echo Dot would just work with the network. Let's make it short: it worked! Yay!

Here's how I did it in macOS Sierra 10.12.1 on my 12″ MacBook:

1. Get your current MAC address of your MacBook and your IoT device. The latter can often be found on the device itself or within the configuration application on your smartphone.
2. Assign the new MAC address to your WiFi device on your Mac or PC.
3. Restart the WiFi device.
4. Log on to the WiFi network and sign in. Make sure the internet access is working properly.
5. When completed, repeat steps with original MAC address. Although a reboot should be sufficient.

macOS Terminal Commands

Here are the exact commands I used to accomplish this (with placeholder addresses; the first one is the laptop's own, the second one is the Echo Dot's):

bash-3.2$ ifconfig en0 | grep ether
	ether aa:bb:cc:11:22:33
bash-3.2$ sudo ifconfig en0 ether aa:bb:cc:44:55:66
bash-3.2$ sudo ifconfig en0 down
bash-3.2$ sudo ifconfig en0 up

Final Thoughts

This simple workaround allows you to authenticate your IoT devices on captive portal networks without needing a web browser interface on the device itself. Once authenticated, simply restore your laptop's original MAC address and both devices should remain connected to the network.

Note: Use this only for devices you are entitled to connect anyway, for example as a hotel guest who is allowed several devices. It is not a way around paying for access.