Best long term cold storage?

[amnesiac]

Hello guys,

I'm looking for an optimale way to store some BTCs for long term.

Being digital nomad, I dont have a proper place to store a paper wallet. I'm quite afraid to lose passwords too, and I want to prevent robbery or a hardware failure (lose of my computer, smartphone, usb key, ...)
I was thinking of a multisig wallet to avoid robbery or to lose access to them in case I'm forgetting a password.

What's my best option?

Thanks

[Lauda]

I'm quite afraid to lose passwords too, and I want to prevent robbery or a hardware failure (lose of my computer, smartphone, usb key, ...)

What you're demanding is a very difficult problem to solve. The best way to make robbery obsolete is to encrypt the wallet (and device - optional) with a long passphrase (which you don't want to use as you're afraid) and the best way to prevent hardware failure is to have multiple backups (e.g. multiple USB keys).

What's my best option?

I don't think there's a singular best option. A simple example would be: [1]Open up a safe-deposit box (or make a hidden/'safe' compartment somewhere in your house) and store some USB sticks (or HDDs, whichever you prefer/have) containing encrypted wallets.

I was thinking of a multisig wallet to avoid robbery or to lose access to them in case I'm forgetting a password.

Multisig 2 out of 3: Wouldn't you have to place 'trust' in additional people (2 in this case)?
[1] - This contains some basic, yet useful information about cold storage. Make sure to read it.

[Barnabe]

What is the lifetime of a USB flash drive (if you don't use it) ? I know that some SD cards wipe themselves after a while, it would be really a shame if you lose your wallet because of this...

[1Referee]

I am storing my cold wallets in USB sticks since the very beginning of 2013 and so far it has worked very well for me. I store all my wallet files in 5 external HDD's and 12 USB sticks. That way I have always access to my wallet files without having to worry that one USB stick or HDD is going to fail. If you want to add an extra layer of protection, then encrypt all data stored on the storage drives and sticks. Solid to the bone!

[vetpet]

You may create armory wallet, then make paper fragmented backup. Send fragments to several your friends or family's members. When you need to restore your wallet, collect "n of m" fragments from your friends and voila! You may also store paper backup in your deposit box in bank if you trust to bank and to your government

[amnesiac]

The best way to make robbery obsolete is to encrypt the wallet (and device - optional) with a long passphrase (which you don't want to use as you're afraid) and the best way to prevent hardware failure is to have multiple backups (e.g. multiple USB keys).

I guess multisig is making the robbery obsolete, I can have one key stollen, but probably not two at the same time... Multiple backups increase the chances of robbery, if not encrypted. And yes, encryption make me scared of myself forgetting how to access to it 

I don't think there's a singular best option. A simple example would be: [1]Open up a safe-deposit box (or make a hidden/'safe' compartment somewhere in your house) and store some USB sticks (or HDDs, whichever you prefer/have) containing encrypted wallets.

As said before, being digital nomad, I dont have fix house... I could get a safe somewhere I guess, but if I can avoid to pay for that, or ask banks to keep my btcs, better.

Multisig 2 out of 3: Wouldn't you have to place 'trust' in additional people (2 in this case)?

Yes I can have 2 trustable people. But... What's about one key on a ledger wallet (with me), one on copay for example, and one in my emails?

For being hacked, the hacker would need to have access and to my copay account and to my mails. If I'm losing my copay password, or my ledger, or access to my mail / mail compromised, I can still move my BTCs to a new wallet.

That way I can keep access to my BTCs from anywhere in the world, and I'm guessing they are safe from a hardware failure or robbery. Am I wrong?

[Lauda]

I guess multisig is making the robbery obsolete, I can have one key stollen, but probably not two at the same time... Multiple backups increase the chances of robbery, if not encrypted. And yes, encryption make me scared of myself forgetting how to access to it  

The best thing that makes robbery obsolete is strong encryption. After a certain length has been reached (and difficulty) they would not be able to acquire your funds even if they could use all of the computing power on Earth in an attempt to crack it. With "forgetting how to access it" you mean forgetting your passphrase, or? I can't really think of good advice for 'backing up a passphrase'. Maybe you could split it into two pieces (2x2 backups) and store them somewhere as well.

As said before, being digital nomad, I dont have fix house... I could get a safe somewhere I guess, but if I can avoid to pay for that, or ask banks to keep my btcs, better.

I doubt that there's a free safebox that is actually 'safe'. I recommend paying for these services.

Yes I can have 2 trustable people. But... What's about one key on a ledger wallet (with me), one on copay for example, and one in my emails?

Wouldn't you still need to memorize multiple passwords to use all of those?

That way I can keep access to my BTCs from anywhere in the world, and I'm guessing they are safe from a hardware failure or robbery. Am I wrong?

Nothing is technically safe from hardware failure IMO, there are life expectancies and device failure rates that variate depending on device type and product. This is why it is recommended to have a minimum of two backups.

[amnesiac]

You may create armory wallet, then make paper fragmented backup. Send fragments to several your friends or family's members. When you need to restore your wallet, collect "n of m" fragments from your friends and voila! You may also store paper backup in your deposit box in bank if you trust to bank and to your government

Yes this could make the deal I guess.

The best thing that makes robbery obsolete is strong encryption. After a certain length has been reached (and difficulty) they would not be able to acquire your funds even if they could use all of the computing power on Earth in an attempt to crack it. With "forgetting how to access it" you mean forgetting your passphrase, or? I can't really think of good advice for 'backing up a passphrase'. Maybe you could split it into two pieces (2x2 backups) and store them somewhere as well.

Yes I mean forgetting the passphrase / password. If it's a password, I can forget it; if it's a passphrase, I have to store it somewhere... this increase the robbery chances, or the chances to lose it. Splitting it in 2 if a good idea to avoid robbery / losing it.
I dont want to find myself in that position : https://www.reddit.com/r/Bitcoin/comments/4qtigi/15_btc_reward_for_the_person_who_can_help_find/

I doubt that there's a free safebox that is actually 'safe'. I recommend paying for these services.

Yes, that's why I would like to avoid these services ^^

Yes I can have 2 trustable people. But... What's about one key on a ledger wallet (with me), one on copay for example, and one in my emails?

Wouldn't you still need to memorize multiple passwords to use all of those?

Yes, but the odds to lose two passwords at the same time are smaller than losing a unique one. Specially I dont think I would forget my email password 

[mobnepal]

All the bitcoin address you generate in internet may not be ideal for storage of bitcoin for longer term if the amount is so much.
You better download https://github.com/pointbiz/bitaddress.org and store it in any folder in a new computer without any online connection or USB stick attach (better to use just formatted pc/laptop). Than open bitaddress.org.html file in browser and generate bitcoin address, no any internet is needed. Save that or print that paper wallet you get. And only copy that bitcoin address to one plain text and delete that paper wallet file .pdf you get from the script. Now only insert USB disk where you have to copy the plain text file with btc address you created before.

Than use that address to send bitcoin to it, i think this is the good way to store bitcoin for long term and most secure cold storage paper wallet method exist. Correct me if there will be a chance of lossing private key in the above method, i am also also thinking to store for long term with the above method.

[DoublerHunter]

All the bitcoin address you generate in internet may not be ideal for storage of bitcoin for longer term if the amount is so much.
You better download https://github.com/pointbiz/bitaddress.org and store it in any folder in a new computer without any online connection or USB stick attach (better to use just formatted pc/laptop). Than open bitaddress.org.html file in browser and generate bitcoin address, no any internet is needed. Save that or print that paper wallet you get. And only copy that bitcoin address to one plain text and delete that paper wallet file .pdf you get from the script. Now only insert USB disk where you have to copy the plain text file with btc address you created before.

Than use that address to send bitcoin to it, i think this is the good way to store bitcoin for long term and most secure cold storage paper wallet method exist. Correct me if there will be a chance of lossing private key in the above method, i am also also thinking to store for long term with the above method.

That's a great idea but i'm wondering how can i withdraw that stored bitcon if i want . Because i also want to store bitcoin for long term soon because now i'm collecting and saving bitcoins as much as i can. I hope i get a reply . Because i never tried any kind of cold storage so i'm confused  .

[mobnepal]

That's a great idea but i'm wondering how can i withdraw that stored bitcon if i want . Because i also want to store bitcoin for long term soon because now i'm collecting and saving bitcoins as much as i can. I hope i get a reply . Because i never tried any kind of cold storage so i'm confused  .

Blockchain.info atleast have option to import bitcoin address through private key to your wallet. Check the option in imported addresses page inside blockchain.info wallet, but you shouldn't import private key unless you like to send coin from that address.

[Lauda]

You may create armory wallet, then make paper fragmented backup. Send fragments to several your friends or family's members. When you need to restore your wallet, collect "n of m" fragments from your friends and voila! You may also store paper backup in your deposit box in bank if you trust to bank and to your government

Yes this could make the deal I guess.

That's an interesting suggestion and similar to 'n of m' multisig. Keep in ind that paper can get easily damaged and lost as well. I wouldn't just give them the paper unprotected.

Splitting it in 2 if a good idea to avoid robbery / losing it.

I guess it depends on the persona. I'm definitely not a fan of "long term cold storage" that is not attended. Even the sharpest minds are at risk of forgetting their passwords over a long amount of time if they don't use it at all.

Yes, but the odds to lose two passwords at the same time are smaller than losing a unique one. Specially I dont think I would forget my email password  

Well, that is true. However, you have to remember 3 passwords which becomes a bit harder unless they are similar (which would defeat the purpose of using multiple passwords in the first place). As said, there's definitely not a singular 'best' method. You'd have to evaluate these suggestions and try finding a solution that fits your persona.

Blockchain.info atleast have option to import bitcoin address through private key to your wallet.

The recommended practice is staying away from trash such as Blockchain.info, not the other way around.

[Barnabe]

You may create armory wallet, then make paper fragmented backup. Send fragments to several your friends or family's members. When you need to restore your wallet, collect "n of m" fragments from your friends and voila! You may also store paper backup in your deposit box in bank if you trust to bank and to your government

What if friends and family share their parts, would it be possible for them to retrieve your wallet against your will ? The system seems nice, but it may depend too much on the human factor (which is usually the weak point in any security-sensitive system).

[BitcoinNewsMagazine]

You could buy a Trezor and take control of your private keys. Trezor has the ability to encrypt your 24 word seed with a passphrase, so the seed is useless to a thief without the passphrase. Store the 24 word seed in several places and keep the passphrase in your head. If your memory is not that great this would not be a good solution for you though.

[calkob]

Paper wallets are the way to go in my opinion, although the new hardware wallets sound like the ticket as well

[Altynbekova]

What is the lifetime of a USB flash drive (if you don't use it) ? I know that some SD cards wipe themselves after a while, it would be really a shame if you lose your wallet because of this...

A flash drive (from a brand is a good option) but make sure to use 2 in case your old one is damages.
If you got 5 bitcoin, spending 20 dollar on a flash drive is a very small investment.

[amnesiac]

You could buy a Trezor and take control of your private keys. Trezor has the ability to encrypt your 24 word seed with a passphrase, so the seed is useless to a thief without the passphrase. Store the 24 word seed in several places and keep the passphrase in your head. If your memory is not that great this would not be a good solution for you though.

Good luck to remind a passphrase you setup 5 years earlier.

[extrabyte]

If you lose your hardware wallet does not mean that you lost your bitcoin, through trezor or ledger you write down the 24-words seed and in case you lose you can recover using electrum or any other wallet which support this technology (except trezor which you should buy another one to recover your bitcoins). An online wallet greenaddress support multi signature and 2FA, take a look at greenaddress.it

[NeuroticFish]

Generate a paper wallet.

Make a rtf document with a lot of text. You can use some documentation for this purpose. Remove all the bold from it.
Set in bold here and there the characters that make your wallet's private key.

Put that document (maybe compressed with password - 7zip with sha) onto cloud, but not dropbox. Instead find a cloud that keeps the data encrypted (like tresorit does).

Complicated enough?

[ebookscreator]

What is the lifetime of a USB flash drive (if you don't use it) ? I know that some SD cards wipe themselves after a while, it would be really a shame if you lose your wallet because of this...

A flash drive (from a brand is a good option) but make sure to use 2 in case your old one is damages.
If you got 5 bitcoin, spending 20 dollar on a flash drive is a very small investment.

Honestly its not a good option to choose usb flash drive because it can destroy or damage even you are not using it.. i i have many flash drive here since i dont use some of them till now some of the usb is not working anymore even i didnt use it.. so beware about this move better to look for other way to save your bitcoins.