No password for wifi?

I just got my sparkcore setup and it is working well with the app. What I found really strange is that the core did not require a password to work on my password protected wifi network.

Can anyone explain how this works?



Hi @simonpuleo

Smart Config works by have the core listen for broadcast packets in a process explained here:


Basically the core uses UDP and algorithms that bypass encryption?

I am a CEH, to me this device could be used in malicious ways.

Why would a consumer accept a device that they could not securely attach to their network ?

This technology is incredible and breaking ground, don’t get me wrong.



Hi @simonpuleo

The TI CC3000 is listening for a particular pattern of UDP packets that the hosts computer broadcasts. These broadcast packets have AES encrypted information about the SSID, encryption type, and password using a shared secret that is common for all cores that Spark sells. Since these packets are only sent by the host computer during the listening phase of setup, the time where an attacker with knowledge of the Spark AES key could gain the network credentials is limited.

If you want to, you can change this AES key on the Spark and in Tinker. You could even have a different AES key per core in an consumer application.


Just to be 100% clear, it’s not bypassing encryption - the host device (that is already part of your secured wifi network) is sending packets using the full wifi network security that’s already established. The spark core and other devices outside of the secured network can see the length of the packets, but not their content.

The smart config can send opaque packets of varying length, and uses modulating packet length as a way to send data to devices outside of the network. Communication is one way only. The data recovered by decoding this modulating packet length is the SSID and passkey encrypted with the pre-shared AES key.

So the spark isn’t gaining access to your wifi network without a password. Rather, an alternate encrypted, one-way communication channel is set up between the two devices to allow secure transmission of the SSID and passkey (as secure as AES is and the handling of the pre-shared secret.)

I’m not a security expert, so I hope that’s clear!