Topic: Storing BTC/LTC long term in safe deposit box - page 2. (Read 3649 times)

Some dude engraved part of his private key onto a ring that is on his finger. Some people have dog tags around their necks with the private key engraved. Some people have strips of cloth with embroidered private keys.

A lot of people have paper backups with QR codes printed. I suggest inkjet and impact dot-matrix printers using carbon paper. You could laminate it as well, but that might not be needed.

Well cared for books last centuries.

My simple solution is to just print them on paper, in large enough font size, QR code optional. Then put it in a folder, then put that folder in an envelope, then hide that thing behind a painting or something I'm sure you can think of.

Check back once a year or so, then re-print.

Sooner or later, I might get my own embroidery machine or an engraving machine. Until then, any cheap printer will work.

If you have bitcoins at an exchange, you don't have them.  The exchange does.  Hopefully they won't lose them and they will give them back to you when you ask them to.

There is actually no such thing as 'having bitcoins on a flash drive'.  There is actually no such thing as a bitcoin.  It is just the summation of value assigned to and removed from a particular address through the entire history of the Bitcoin system.

The only way to assign value away from an address is to use the private key for that address to 'sign' a desired transaction.  Anyone who has the private key for an address can do this (and nobody who does not have the private key can do it!)  Staying secure means:

 - not losing the private key to an address with value assigned (e.g., deleting your wallet file or losing your laptop.)

 - not having the private key known to anyone you don't wish to know it (e.g., like a hacker.)

 - not accidentally transferring value away from an address (e.g., brain-fart of being tricked.)

A 'wallet file' is just a collection of private keys for one or more addresses.

How does the public and private keys work? If I leave my bitcoins on an exchange can I write down the key so that others can't steal them?

If I write the private key on a piece of paper ("paper wallet"?) but then leave the bitcoins on a flash drive and get the drive stolen, then does that mean that i could use the private key to retrieve them or just that the theif wouldn't be able to use them?

Heh, this is key too.  Security through obscurity DOES have merit (just maybe not in computer code).

It's a legitimate argument that multiple backup/deep-store techniques create multiple failure modes as well.  I won't argue on way or the other.

One's security regime is a personal choice.  Probably the best advice would be to simply understand Bitcoin (or whatever) well then tailor a solution which fits one's situation.  And then keep one's mouth mainly shut about it.

No one method is failsafe.

Metal can be stolen or lost.
Locations of rocks can be forgotten, or they can be covered with a new supermarket 20 years from now.
Foundations can be destroyed in an earthquake.
Closet walls can be destroyed in a fire.

Bottom line is, I always make sure to store any Bitcoin backups of significant value in at least two ways, to protect against one of those failing.

In the event of war or some other crisis, you can be sure bank vaults will be emptied..

Agreed, for long term storage, forget about hardware and software. A private key is all you need. Hardware and software will change over time, but the public/private keypair is fundamental to bitcoin.

Agreed, as with gold and silver, bitcoin is a way of getting out of the banking system. I wouldn't be in a hurry to put your money back in.

Rather than storing anything in a safe deposit box in a bank - I wood go out in the woods and put everything in a 'survival box' and dig it down somewhere. Seems safer than the bank option to me. To reduce risks, you may even split it out (several wallet - several boxes). Then GPS-mark those places, and come back in 5 years.

The problem with using hardware is that it changes and it could fail due to heat or moisture or rust or...

Download vanitygen and create a public and private key.

Write them down or etch them into metal or stamp it into something, etc.

Send your BTC to the public address and you are all set.

You could even scratch the private key into a rock and bury it in your yard or whichever. Etch it into the foundation in your home. Carve it into the wall in the closet then cover with wall paper...

plenty of options for just saving a string of characters

I wouldn't feel so comfortable storing an bitcoin wallet in a bank. In the future, they could tax you or take your stuff or whatever. One thing we should learn from bitcoin is to trust many peers not one and certainly not a bank. No? Can't you think for a better place to store a paper wallet?

You'll need to preserve the software you used to create and manipulate your Bitcoin stash. Do not assume that it will not change. It will change and none of the current developers have the resources to properly test their current versions for backward compatibility with all previous versions of itself.

"Dependencies" means all the software required to build the software above. Edited to add: For exampe: if you used Armory on Ubuntu 12.04 then you need to save all the Ubuntu 12.04 plus the source code to the exact version of python, swig, Qt-toolkit and whatever else is being used to rebuild Armory.

I cannot be more specific, because I don't know the answer myself. You'll need to either learn this yourself or pay somebody to do the research for you. You can either do it now cheaply or later much more expensively.

When you say software and dependencies can you be more specific?

I do not understand why i would want a netbook or laptop to take up additional space in my safe deposit box? Those have hard drives and or SSD.. I think a CD with the wallet.dat file and a paper wallet equivalent of that (if i can both) would be fine... Maybe im missing something? When i decide to use or sell them years from now wouldnt i just need to download the bitcoin client, sync with the block chain and then add the wallet.dat file to the bitcoin program directory?

How would using Armory be more secure than doing what i recommended in the first post? And my worry about using Armory is what if it is no longer supported years from now and i cannot transfer funds out of the Armory to a BTC client?

Hardware isn't really required. It is a commodity and easily virtualized or emulated. Store all the software required to access your wallet, including all the dependencies.

Also, of the generally available optical media DVD-RAM are the longest lasting and have the lowest failure rates.

I started out before there was any wallet encryption and thus rolled my own using openssl.

It might be worth considering making multiple deep storage wallets sized for where you think the price might go.  I did this and am very happy for it.  One possible recovery method is using the wallet import features of one of the on-line wallet services.  I personally would feel queezy about doing this for very high-value sizes even though the value would only be under control of someone else briefly.  Who knows if a 'glitch' might crop up when someone entrusts them with $100k in one shot?

For one, I can have a systematic naming scheme representing the total value, date, etc.

For two, I can sell an entire wallet.dat and that can be handy in some instances.

For three, I can instruct my heirs (who know that I've got some value in the solution and will find my backups in my safe deposit box) that if they need to retain a professional to retrieve the value, to do so incrementally.  Thus they cannot be fully ripped off in one shot by a dishonest geek.

FWIW, I recently took a cold storage wallet made with bitcoind compiled in the middle of 2011 and it worked fine in an 0.8.x pre-compiled linux build of bitcoin-qt.  (This new build also synced in under 24 hours, and uses modest resources on a powerful system so LevelDB is impressing me thus far.)

If you are using paper wallets, make sure to use ink that doesn't fade away over time.

Using flash drives or solid state drives for years is not good idea. Flash cells discharges over time and slowly lose data. According to paper released by HP the time can be from few months with worn SSD drives written in elevated ambient temperature to 8 years (for SLC flash drives) from my own experience. Contrary good quality CD-R stored in controlled environment have lasted 15 years and counting.

Take a look at Armory client with the deterministic wallet paper backup. Print many copies and store them in separate places.

Storing anything in bank is not good idea. It can be confiscated by government, stolen by robbers or destroyed in fire. Hide the paper backups in old way like deposits of gold.

I think as a way to access them in an emergency. Since you will need a computer to get to them. You could buy any cheap used netbook for that purpose.