Best way to use Shamir's Secret Sharing

[madmat]

I want to use Shamir's Secret Sharing algorhythm to make a paper wallet in a way some risks are lowered : paper wallet lost, burnt or stolen.

My first idea was to use https://encryptedbitcoinwallet.com/ with 5 shares and 3 required and then to set in 5 envelopes one share with the secret and one bip38 paper wallet.

But i do not see clearly the benefit of sharing a passphrase versus directly sharing the bitcoin private key.

If someone could clear my mind on the subject.

[GigaCoin]

I want to use Shamir's Secret Sharing algorhythm to make a paper wallet in a way some risks are lowered : paper wallet lost, burnt or stolen.

My first idea was to use https://encryptedbitcoinwallet.com/ with 5 shares and 3 required and then to set in 5 envelopes one share with the secret and one bip38 paper wallet.

But i do not see clearly the benefit of sharing a passphrase versus directly sharing the bitcoin private key.

If someone could clear my mind on the subject.

Scam

[madmat]

Scam

Tell me more!

[iceburn2003]

I am a bit late to this post, but I am the creator of https://encryptedbitcoinwallet.com, and for what it is worth: The site is not a scam.

Trust is difficult, but I have published the website under my real name. I have created the site as a fork of bitaddress.org to make it easier for folks to analyze my code. The project is available on Github at https://github.com/exception386/encryptedbitcoinwallet.com

To be extra safe you can always download a copy of Encrypted Bitcoin Wallet and run it from an offline computer.

Thanks,
Jeff Hockema

[jonald_fyookball]

I am a bit late to this post, but I am the creator of https://encryptedbitcoinwallet.com, and for what it is worth: The site is not a scam.

Trust is difficult, but I have published the website under my real name. I have created the site as a fork of bitaddress.org to make it easier for folks to analyze my code. The project is available on Github at https://github.com/exception386/encryptedbitcoinwallet.com

To be extra safe you can always download a copy of Encrypted Bitcoin Wallet and run it from an offline computer.

Thanks,
Jeff Hockema

Offline address creation should be done even if site is trustworthy because of possibility of viruses.

[Ron~Popeil]

When you call someone a scam you should have some evidence to back it up. The constant cries of scam don't help anyone.   

[Jan]

I want to use Shamir's Secret Sharing algorhythm to make a paper wallet in a way some risks are lowered : paper wallet lost, burnt or stolen.

My first idea was to use https://encryptedbitcoinwallet.com/ with 5 shares and 3 required and then to set in 5 envelopes one share with the secret and one bip38 paper wallet.

But i do not see clearly the benefit of sharing a passphrase versus directly sharing the bitcoin private key.

If someone could clear my mind on the subject.

SSS is superior to any kind of password encrypted private key scheme. You should check out Mycelium Entropy (https://www.indiegogo.com/projects/mycelium-entropy) which supports SSS (BIP in progress).

[Tenarlty]

I use ssss. Very versatile and easy to use, and the project even has a Bitcoin donation address.

[Tenarlty]

I don't know if it runs on Windows, but making the splits on a live Linux booted from an optical medium makes sense anyway.

[grue]

Don't bother using Shamir's Secret Sharing, just use multisig transactions. It's part of the bitcoin protocol so you don't need a tool to recombine the keys.

[madmat]

Don't bother using Shamir's Secret Sharing, just use multisig transactions. It's part of the bitcoin protocol so you don't need a tool to recombine the keys.

What are the tools you use for multisig ?

[grue]

What are the tools you use for multisig ?

It can be done with only bitcoin core: https://gist.github.com/gavinandresen/3966071

[madmat]

What are the tools you use for multisig ?

It can be done with only bitcoin core: https://gist.github.com/gavinandresen/3966071

It is not very user friendly if you have to script it. I think mycelium is about to add multisig paper wallet support for their entropy thing. But i don't have any date for that.

[hashman]

Yeah year of the multisig and all and here we are still using bitcoind command line with 1000+ character lines based on gavin's 18 month old instructions.  

Fortunately there's a nice javascript tool also in the wild which works on your offline computer:

https://github.com/OutCast3k/bitcoin-multisig/



Or you could go the SX route..  have you tested that recently grue?  

[gtsvani]

I use ssss. Very versatile and easy to use, and the project even has a Bitcoin donation address.

I how do you use it!! I have been trying so hard! Do you have to open it on a windows machine and if so how?