Access the Internet over Thread from Android Things

[MSohm]

I'm trying to connect to the Internet from Android Things connected to an NCP through the OpenThread Border Router.

1 Raspberry PI running RaspPi_OT_Border_Router_Demo_v2.0.0-1.alpha. This device is also connected to IPv4 ethernet connection to the Internet.
2 Raspberry PIs running Android Things
Each device is connected to a Nordic nRF52840-PDK over USB.

I am able to run the CLI example with an nRF52840 connected to my computer and ping 64:ff9b::0808:0808, so Internet connectivity over thread appears to be working.

Using the Android Things LowPan sample and Thread network created by the Border Router, the two things devices are able to see and connect to one another**.

I then modified the LowPan sample to connect to servers outside the Thread network (making a socket connection to a public web server), but am not able to connect to anything.

If I try to connect to a public external IPv4 address (converted to IPv6 with the 64:ff9b:: prefix) I get:

android.system.ErrnoException: connect failed: ENETUNREACH (Network is unreachable)

If I try to connect to a public host name I get:

android.system.GaiException: android_getaddrinfo failed: EAI_NODATA (No address associated with hostname)

Has anyone gotten Android Things working in this way?  Is there any special configuration required on the Border Router?

** I had to change the name of the Thread Network that is configured by default, otherwise the Android Things devices threw an exception about invalid characters.

[Bjørn Kvaale]

Would it be a possibility to use this demo to use the Raspberry Pi as an internet gateway (link 1, link 2, link 3)? It should work out of the box with a Nordic Thingy:52, but could most likely easily be tweaked to work on a 52840 dk.

[MSohm]

That example is Bluetooth, so a bit different from what I'm trying.  Since the Android Things device is connected to the Thread network Border Router, it should be able to access the Internet directly.

I could create something like what is shown in that example, where there is a server (Node.js for example) listening on the Border Router that acts as a gateway application to the Internet.  However, the Border Router should be able to do this on it's own as that is what it is designed to do.

[MartinBL]

Hi,

Sorry for the delayed response. Bjørn is traveling at the moment, but I'll try to help you out from here.

Have you made any progress? I have asked for a comment from the Thread team. I'll keep you posted. 

[MSohm]

I didn't get any further along getting the Android Things (AT) device to connect to the Internet.  For now I'm considering having the app on the AT device connect to an app on the Border Router, which then relays data to the destination server.  But that isn't the ideal setup.

[MartinBL]

Hi,

I have been in contact with the Thread team, but unfortunately they don't know why you get those exceptions and they are short on resources these days and don't have time to dig into it. I don't have the necessary HW to reproduce it myself either, so I'm afraid you are on your own on this one. 

-Martin