<p>Have a look at byteball (<a href="http://byteball.org" rel="nofollow noreferrer">http://byteball.org</a>). It supports n-of-m wallets out of the box which can be used to implement a basic 2FA mechanism (2-of-2 with your desktop and your smartphone, for example.)</p>

<p>It also has a chat mechanism built in, which can be used to communicate between the devices and which would probably enable you to do what you intend.</p>

<p>There are a number of other interesting features listed at the web site.</p>

CC BY-SA 3.0
2017-05-05T21:18:34.970Z
2017-05-05T21:18:34.970Z
Hans-Martin Mosner
<p>Which coins have the ability to offer a 2 factor authentication feature where it requires a secondary approval mechanism in order to spend from an address? </p>

CC BY-SA 3.0
2017-05-05T15:58:46.183Z
How would that work? Blockchains can't send emails or receive SMSses. The transaction sender has to prove to the rest of the system that a spend was authorized. You could use multisig pretty much anywhere, and require a signature from both a desktop system and a phone, for example, but that's it.
Pieter Wuille
CC BY-SA 3.0
2017-05-05T16:34:10.210Z
Is there a platform that lets you have a multi-signature setup on your phone and desktop? I guess how would one do this for a Bitcoin transaction. Say I made a transaction on my desktop and then needed approval on my phone.    How does my phone know that my desktop is making a transaction?
Patoshi パトシ
CC BY-SA 3.0
2017-05-05T16:49:59.063Z
You can use bitcoind's raw transaction interface to do this. It's your responsibility to create a valid transaction that the network accepts. The currency or blockchain can't help you coordinate between the two signing devices.
Pieter Wuille
CC BY-SA 3.0
2017-05-05T16:52:32.050Z
To be clear: I think there are is currently no consumer-friendly ways to do what I'm describing. But that's due to a lack of available software, not a missing feature of the chain.
Pieter Wuille
CC BY-SA 3.0
2017-05-05T18:11:15.630Z
thanks pieter. this is something i'm trying to solve... im not sure how this can be done as the transaction creator needs to somehow let the other device know it needs to sign this new transaction it created. will investigate further.
Patoshi パトシ
<blockchain><decentralization><two-factor-authentication>
Which coins offer a 2 factor authentication feature built into the blockchain without a centralize authority?
Patoshi パトシ
# Which coins offer a 2 factor authentication feature built into the blockchain without a centralize authority?

(Asked by: username_0 on 2017-05-05)

Which coins have the ability to offer a 2 factor authentication feature where it requires a secondary approval mechanism in order to spend from an address?

**Tags:** blockchain, decentralization, two-factor-authentication

> **Comments:**
> **username_1**: How would that work? Blockchains can't send emails or receive SMSses. The transaction sender has to prove to the rest of the system that a spend was authorized. You could use multisig pretty much anywhere, and require a signature from both a desktop system and a phone, for example, but that's it.  
> **username_0**: Is there a platform that lets you have a multi-signature setup on your phone and desktop? I guess how would one do this for a Bitcoin transaction. Say I made a transaction on my desktop and then needed approval on my phone.    How does my phone know that my desktop is making a transaction?  
> **username_1**: You can use bitcoind's raw transaction interface to do this. It's your responsibility to create a valid transaction that the network accepts. The currency or blockchain can't help you coordinate between the two signing devices.  
> **username_1**: To be clear: I think there are is currently no consumer-friendly ways to do what I'm describing. But that's due to a lack of available software, not a missing feature of the chain.  
> **username_0**: thanks username_1. this is something i'm trying to solve... im not sure how this can be done as the transaction creator needs to somehow let the other device know it needs to sign this new transaction it created. will investigate further.  

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## 1 answers

### Answer by username_2 on 2017-05-05. Score: 1

Have a look at byteball (<http://byteball.org>). It supports n-of-m wallets out of the box which can be used to implement a basic 2FA mechanism (2-of-2 with your desktop and your smartphone, for example.)

It also has a chat mechanism built in, which can be used to communicate between the devices and which would probably enable you to do what you intend.

There are a number of other interesting features listed at the web site.


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