Hi. I'm Andy, one of the developers on the AirGap project.
That's exactly what it is.
Than it's much better to call it with it's real name instead of inventing something like Social recovery feature.
It is also important for compatibility to say if your Secret Shamir Scheme is compatible with one that is available in other hardware wallets like Trezor Model T and Keystone wallet.
There are 2 reasons why we called the feature "Social Recovery" instead of "Shamir's Secret Sharing".
1. The term "Shamir's Secret Sharing" is known in some parts of the community, but because of the lack of a clear standard (at least at the time when we added the feature many years ago), we didn't want users to make false assumptions, eg. regarding compatibility with other implementations (there were a few CLI tools but they were not compatible with our implementation).
2. The term "Social Recovery" is clearer for less technical users.
As already mentioned above, our scheme is not compatible with any other implementation, eg. Trezor or Keystone. The main reason is that our implementation is older than the finalised SLIP-39 standard, which is used by Trezor and Keystone.
The reason we did not change to the SLIP-39 standard after it was finalised is because SLIP-39 does not allow to split up an existing 12 / 24 word mnemonic. So it does not allow you to go from BIP39 mnemonic => Shamir Shares => BIP39 mnemonic. With our implementation, this is possible.
But now that the SSKR standard was defined by blockchain commons, we are planning to adopt it in the near future.
Having only the seed phrase is a single point of failure. Introducing a mechanism to recover the wallet even if you lose the seed phrase eliminates this
Yes it is, unless you add multiple passphrases, but we are talking about improving something and removing single point of failure, that was not accomplished with SSS because one guy controls everything.
You are right, SSS does not remove the single point of failure regarding mnemonic usage, but it does solve the single point of failure regarding secret backup and storage.
In the future, we will be implementing something more standardized like SSKR and Seed XOR.
That is better, but I don't know who currently uses this except maybe Coldcard.
As far as I know, only Coldcard supports Seed XOR at the moment. Hopefully more wallets will follow soon.
Can you make a comparison between your Social recovery feature VS Shamir Secret Sharing VS Threshold Signatures Schemes or Multi-Party Computation, for example? Why are your methods better and recommended compared to the ones mentioned? MPC is something I recently heard about, but it's in connection with an altcoin that I don't want to be accused of shilling if I mention it. It's easy to find on the first page of a Google search and the project begins with "Q".
As mentioned above, the Social Recovery feature is just a name we use for our implementation of the Shamir's Secret Sharing scheme. I don't know much about Threshold Signatures or Multi-Party computation so I can't talk about them. But from what I've heard they sound very interesting and could solve a few problems.
