Samourai Wallet, one of the best wallets out there, recently announced that sending Bitcoin without a connection to the internet would be possible in the short future. Yesterday, they delivered what they promised using their TxTenna device.

The transaction doesn’t work entirely offline, but it works in a secure and easy way that could pave the future for Bitcoin offline transaction. Firstly, to be able to send Bitcoin without internet or data connection – a user has to rely on the goTenna mesh network.To start, the Samourai Wallet creates a signed transaction, which he pass to the TxTenna app. The transaction is broadcasted to nearby mesh nodes trough a paired goTenna mesh device. The mesh nodes receive the transaction and pass it to the nearby nodes until a node with a TxTenna internet connection is found. That node proceed and forwards to transaction to the Bitcoin network.

A twitter user called Coinsure decided to test this and send a Bitcoin transaction using this technology.

Over the weekend I sent a bitcoin transaction to a relay 12.6km away with no cell network or internet connection. Here's a tweetstorm about how I used @gotenna and @SamouraiWallet to do it — ℭoinsure (@Coinsurenz) October 16, 2018

The main objective was to try and use 5 GoTennas to send a transaction from 19.2 km – as one goTenna have a maximum rage in an open environment of 6.4 km. He first set up his perfect route in Auckland, New Zealand – a route where the nodes could receive & forward transaction without an issue

I used google maps to find a route in my home town(Auckland, New Zealand) that connected high ground points as close to 6.4 km apart as posssible. The route- One tree hill-Mt Albert-Waikumete Cemetary-Parkinson Lookout- is shown below pic.twitter.com/ZGFz1vM2bn — ℭoinsure (@Coinsurenz) October 16, 2018

The equipment used was 4 goTennas ( which costs around $26 usd), an android smartphone with no cellular or wifi connection and a few other things to mask the goTennas so no one could interfere in his project. His phone would work as a radio device with a bitcoin wallet and utxos while his girlfriend’s phone would be connected to the internet and would act as the final node that will forward the transaction to the bitcoin network The first transaction was from One Tree Hill to Mt. Albert – a distance of 5.61km. The transaction was successful.

First transaction was One Tree Hill to Mt.Albert. Direct gotenna to gotenna. Transaction sucessful, Total distance 5.61km. pic.twitter.com/q5yZFV5hId — ℭoinsure (@Coinsurenz) October 16, 2018

The second transaction was from Waikumete cemetery to Mt Albert and then sent to his girlfriends phone. The transaction was successful and the total distance until now was a total of 12.67 km.

Next I made my way to Waikumete cemetery. This transaction would be relayed from my gotenna, through the one I had stashed on Mt albert, on to my girlfriends phone and gotenna on One Tree Hill. Transaction successful, one hop of 7.06km and another of 5.61km- total 12.67km. pic.twitter.com/tNgJGgeQMe — ℭoinsure (@Coinsurenz) October 16, 2018

The third transaction was made from the Parkinson lookout – 7.15 km away from the last point. This final transaction failed, perhaps due to an app crash experienced by his girlfriend’s phone. But however, the experiment was pretty productive. According to Coinsure, around 1120 square km could be covered with using 37 units of goTennas.

This is the -very- rough diagram I drew up. Not exact but you get the idea. Correction to earlier numbers- 37 units and 1120square km covered pic.twitter.com/oiCahTFoBG — ℭoinsure (@Coinsurenz) October 16, 2018

The test was almost fully successful. Even if the last transaction didn’t passed, this could have been due to the app crash. However, this experiment proves how useful Bitcoin can be and how it will work even in the harshest conditions.In addition, goTennas doesn’t have a really wide transaction range. But another devices can be created that will probably allow someone to send Bitcoin for over 20km without using any internet connection. This is just the beginning, and the future looks bright.

A better explanation of how TxTenna works with Bitcoin can be found here:

1/ TxTenna, an application of mesh networking with Bitcoin transactions, is on the horizon thanks to @SamouraiWallet and @gotenna. This is super exciting. But what does it mean exactly? An intro to mesh networks and goTenna: — Yassine Elmandjra (@yassineARK) October 8, 2018

And the conclusion is loud and clear – you don’t need internet to use Bitcoin.

Image Source: InTheMesh