Quote from: lukaexpl on August 28, 2017, 08:04:17 PM

I am paranoid by design and by professional deformation.

Suppose you have the following tools available:

1. two Trezor hardware wallets
2. offline bootable PC with Ubuntu
3. bitaddress.org site burned to a CD
4. BIP39 passphrase and mnenomic code generator burned to CD
5. passguardian.org Shamirs secret sharing page burned to CD
6. offline printer to print and laminate paper wallets
7. metalstamps to stamp seeds/keys to metal plates if need be
8. two rented safe deposit boxes in two banks in two different European jurisdictions

How would you go about designing a "perfect" cold storage that should fulfill the following criteria:

1. be resistant to my death hence inheritable
2. be reistant to my amnesia
3. be resistant to being denied physical access to both safe deposit boxes
4. be resistant to malevolent staff opening the contents of the safe deposit boxes
5. be resistant to goverment confiscation/access denial to your safe deposit boxes

So basically I want no other entity (spouse, underage children, bank staff, evil government officials) to be able to spend my bitcoins as long as I am alive and with a functioning brain.
I also want to be able to comitt to memory a seed or an encryption method that would grant me access to bitcoins if I am not able to access the cold storage in safe deposit boxes.
Ultimately I would need to leave clear instructions in case of my death so that the family would be able to reconstruct access to those bitcoins.

I have some ideas but would like to hear flaws in my design.

1. PAPER WALLET ROUTE

One way to go about it would be to create paper wallets, print them offline, encrypt them with a strong passphrase (for example Diceware generated) using BIP38 and store them in two separate safe deposit boxes.
The secret passphrase would be easy to memorise for me and could be split using sharding into 3 pieces (2 safe deposit boxes and my home for example) so that you would need access to all of those in order to decrypt the paper wallets.

It prevents goverment or the bank staff from spending your bitcoins but if you find yourself unable to access the physical location of your paper wallets you are doomed.

2. TREZOR MNEMONIC SEED

You load your Trezor hardware wallet and stamp the seed on metal plates in a randomly generated order that you put in one safe. In another safe you put an encrypted message that is simply the order in which you have to put the mnemonic seed to be able to access bitcoins. You distribute the passphrase to unlock the order in the same way as in design No. 1.

You carry your Trezor with you (your home) hoping that even if it gets stolen nobody will be able to break the PIN.

This method has the advantage that with some memory technique you should be able to remember the seed yourself and reuse it should you be locked out of access to your safe deposit boxes.

Is all of this an overkill? Are there simpler ways?

Why do we need such thing? Sorry I am new to the concept of cold store. I just want to know why would one need such thing

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