Gotenna and pi zero


#1

I’m thinking of putting a pi zero with my gotenna. I could then leave it on and it could act as a bridge for sms messaging.

Seems a very simple and small way to offer bridging.

Might also look to add a bigger antenna as others have and put it on the roof of the house.


#2

That’s a cool idea! low power and cheap to add a pi zero. How would it bridge to SMS? using the wifi of your house? or would you use something like the Adafruit FONA 808 Mini Cellular GSM + GPS Breakout

Please post more details if you get this working.

In quantity a simple GSM circuit should be pretty cheap. For example, these kids smart watches have GSM and a lot more and cost under $30.

Perhaps someday we’ll see a goTenna mesh model with a SIM slot that can act as an SMS/GPRS/3G gateway without additional hardware.


#3

My first plan is just to join WiFi and send the data via that. Hadn’t thought bout using a GSM module…

Having thought a little more maybe use ESP8266, then it’s even smaller, and less power. Need to look at the SDK I think to see if we can port it over to Raspberry PI and Arduino.

This plan also benefits from not having to take the GoTenna apart. Well not until you want the bigger antenna anyway.


#4

Just a quick note that with goTenna Plus you can network relay into SMS out of the box! (We use Twilio)


#5

I’ve just signed up for a free API key from Twilio. Now I guess I need to figure out the communication from the GoTenna Plus system so I can receive the SMS request and send it over to Twilio.


#6

@Guy can you clarify what you are trying to do?
I feel SMS network relay with goTenna Plus, may be able to give you exactly what you are looking for.


#7

I want to interface with the GoTenna Plus… such that users of GoTenna can use my stationary mesh point to either relay to other Mesh users or via the pi zero out to an SMS destination.

So this is augmenting the goTennna plus system, adding additional relay points.


#8

@Guy oh cool!
goTenna Plus, automatically sends messages to SMS destinations via goTenna Mesh nodes that are paired to phones with access to the internet.
As an example, lets assume you have an old iphone/android device connected to WiFi paired with your goTenna Mesh unit that you are dedicating for relay purposes. With this setup, other Mesh near you, will be able to send messages to SMS destinations via your device.

You can try to replicate the same functionality using Raspberry Pi and replace the phone in the above setup. goTenna SDK is currently only available for iOS/Android. You will have to first run an Android instance on Raspberry Pi.


#9

Yes so I want to keep the Node on-line all the time and then anyone who needs it would be able to use it, both as a mesh node, but also as an SMS uplink. I don’t really fancy leaving a phone attached but a cheap raspberry zero is small, cheap and lower powered enough that I could easily run both from a solar panel and battery.

In order to do this, we need to understand the details of the Pro SMS sending. Which I guess GoTenna aren’t going to share as it would allow people to by-pass the monthly license fee.

The fee I’m guessing is covering the cost of the SMS messaging and licensing of the off-line maps.


#10

Been out of the loop due to work and skydiving BUT this thread is awesome and will get into it in more detail asap! THIS IS AWESOME!


#11

Keep us posted on how dev goes with the Raspberry Pi.

Yes, the $9.99 annual fee, helps us cover the cost of the SMS messaging service we use - Twilio.


#12

It also helps cover the cost of the topo maps we have to license from a maps provider


#13

In order to make this work I need details of the protocol used to forward the SMS.

Also would it be possible to get the source to the API? it would help to port it over to Raspberry PI.


#14

Go download Wireshark. You can use it to sniff the messages going to the goTenna. Android devices since 4.4 can dump a Bluetooth log if you enable it in Developer Options. Then open that log in Wireshark. You just need to design an experiment that let’s you fully reverse engineer the messages. By the way, I believe goTenna uses Bluetooth Low Energy. That makes it simpler as it’s more like a service oriented architecture where you specify services and parameters for those services. You can download an app called nRF Connect and nRF Toolbox to help you explore the goTenna interface. I think you’d want to get the connection going with the goTenna app then use these other apps until you figure out what’s going on at the beginning with handshakes. Not sure you can completely bypass the SDK or get away without using the Pro version, but I suspect you can. It just comes down to the amount of work you’re willing to put into reverse engineering the interface.


#15

Yeah I was hoping to go around the front door and get the source, rather then revere engineering it. Also I’d hope gotenna is using SSL to send data between phone and internet. Now I do have an SSL Bump system in place so I can capture data in clear but it’s a hassle.

GoTenna is also encrypting data, so I’m guessing getting the data off the wires will likely not give the full storey as I can’t decrypt that data.


#16

I also bought 4 Beartooth radios. I can verify that the payload is being transmitted in the clear for those devices, that is they aren’t encrypting the payload before hitting BT. Not sure if the BT connection is encrypted or not since I’m grabbing it before it leaves the phone. For goTenna, I must be one of the last backers since I’m in the bunch of last 200 to go out and haven’t received my goTenna devices yet. Hopefully tomorrow or early next week.


#17

These clowns have been pretty clear their devices do not mesh nor are they encrypted. Someone at my hackerspace backed them just to see how they would compare to the v1 goTenna devices I got last year, and they finally shipped to him this summer and not only are they unencrypted & nonmeshing, they get about half the range as my goTenna Mesh units (didn’t compare them to goTenna v1 as I’ve donated those to my local SAR team). Beartooth also recently advertised on Breitbart (i.e. alt-right launchpad) so they’re on my blacklist for several reasons.


Devices similar to gotenna
#18

What surprises me is that these devices aren’t doing the encryption at all instead relying on the app layer to encrypt. In the case of Beartooth, they are also meshing at the app layer. How do I know? The encryption and mesh capabilities in Beartooth won’t exist until a future app update. Sigh. I work for the military, so I’m used to this stuff being done in the radio firmware. I guess for consumer devices it’s easier to fix mistakes with an app update than a firmware update.


#19

I’d short Beartooth in a second. They started taking preorders for the product you just received in the summer of 2014. They delivered THREE YEARS later and incomplete. I have friends at DARPA who say Beartooth’s team is a joke. Just go long on goTenna. They have released v1 AND Mesh (both with complete features) and the badass looking Pro is coming up in Dec:

The only thing I am still waiting for is the goTenna Mesh SDK… @Rahul_Subramany @danielagotenna @Jin_Gotenna @Raphael when is that out? :slight_smile:


#20

The SDK is already out… you just need to request access.

It’s a compiled framework ready to go.