Author

Topic: Cold Storage Question (Read 252 times)

member
Activity: 125
Merit: 10
October 09, 2018, 12:37:22 AM
#13
You can always use Bitkey as an alternative to cold storage https://github.com/bitkey/bitkey
legendary
Activity: 3808
Merit: 1723
September 12, 2018, 02:39:20 PM
#12
Regarding YouTube videos,

Always use your due diligence because there might be some scam or trick going on.

Look at the video and use it as a general guide but never click on any links presented to you.

It might be a phishing site or might trick you into entering a seed which already is in use like they did with some of the Amazon and eBay listings for hardware wallets and lead to loss of funds.
legendary
Activity: 2758
Merit: 6830
September 07, 2018, 07:56:21 AM
#11
Says video does not exsist
Sorry. I’m traveling and just now saw that I (somehow) put the wrong link.

Here is the working one: https://youtu.be/DQumISxkJsQ
legendary
Activity: 3710
Merit: 1586
September 07, 2018, 07:49:42 AM
#10
you have to install the wallet on the offline device first in order to generate the master public key for the online wallet. see the guide here
legendary
Activity: 3472
Merit: 10611
September 06, 2018, 10:54:41 PM
#9
Thanks for all your help and answers, I am going to do a numbered list, let me know if I am correct on my thinking:

1. Hot wallet is on Desktop with internet
2. Install Electrum on Laptop with internet, watching wallet
3. Install Electrum on Laptop no internet
4. Watching wallet get receive address
5. Hot wallet send to address of watching wallet step 4
6. Cold wallet get receive address
7. watching wallet send to cold wallet address from step 6
8. download transaction go to cold wallet, sign then upload to watching wallet and click braodcast

I think I got all the steps, after all is done, won;t need the hot wallet on desktop, just the watching wallet

1. hot wallet is usually referred to a wallet with keys and everything which is connected to the internet. like your  desktop wallet which you can spend from directly. it is only good if you spend bitcoin regularly in small amounts. otherwise stick to cold storage.
2. true.
3. as long as this laptop never connected to internet in the past and will never connect in the future. you want a clean environment cut off from the rest of the world. this includes internet and any other sort of network like LAN,... and the laptop needs to be clean. try formatting the drives and installing a fresh OS on it for instance.
4. true but basically you give it your master public key which is ALL your addresses even the ones you create in the future.
5. you don't need a hot wallet, you use the step 4 watch only online wallet. in fact you have only 2 wallet instances both with same addresses: 1 cold storage on offline computer which has the keys only + 1 watch only wallet on the online computer which has the public keys and addresses and transaction history but no private keys. your addresses are generated on the offline wallet from the private keys, the online wallet can only have addresses and public keys it doesn't generate them from scratch they were created in your cold storage.
6. as #5
7. you don't send "addresses" you transfer "transactions" between these two wallets.
8. true.

to understand this imagine you have a special pen at home which you never carry with yourself outside of your home and you use this special pen to sign checks. but in order to get the check you need to go to the bank because sitting at home you have no idea what is going on in the outside world and don't know how much money is in your bank account. so you go the bank, get a check from the clerk with the amount,... on it and come back home to sign the check with your special pen. now in order to finalize the money transfer you have to again tell the outside world what you did so you take that check and go back to the bank and give it to the clerk so that he can enter it in their database.
in this scenario
- the bank is your online wallet.
- your home is your cold storage wallet disconnected from the internet
- your pen is your private key which you keep at home and don't let it have any contact with the outside world.
newbie
Activity: 9
Merit: 0
September 06, 2018, 09:42:17 AM
#8
Thanks for all your help and answers, I am going to do a numbered list, let me know if I am correct on my thinking:

1. Hot wallet is on Desktop with internet

2. Install Electrum on Laptop with internet, watching wallet

3. Install Electrum on Laptop no internet

4. Watching wallet get receive address

5. Hot wallet send to address of watching wallet step 4

6. Cold wallet get receive address

7. watching wallet send to cold wallet address from step 6

8. download transaction go to cold wallet, sign then upload to watching wallet and click braodcast

I think I got all the steps, after all is done, won;t need the hot wallet on desktop, just the watching wallet
legendary
Activity: 1624
Merit: 2481
September 06, 2018, 02:56:41 AM
#7
A wallet is just a piece of software which manages your private-/public- keys.

It does not need to be online at any time to be able to 'receive' bitcoins.

Simply install any preferred wallet on your offline-PC (e.g. electrum), verify the signature, create a wallet, backup the seed, and export the xpub (master public key) to your online-pc.

You can afterwards create a watch-only wallet on your online-pc (shows addresses, transaction, balances) but you can't sign transactions since there is no private key imported.

Your offline-pc wont show your current balance. Only your watch-only wallet on your online pc will.


Please do NOT create your seed on your online-pc and delete it afterwards to create a watch-only. This destroys the whole purpose of a cold wallet since your private keys are supposed to NEVER touch an online-pc.
If you are creating the seed on your online-pc you are assuming your online-system and network is completely clean. And that's not an assumption you should make when setting up cold storage.
legendary
Activity: 3808
Merit: 1723
September 06, 2018, 02:20:04 AM
#6
If you are extremely paranoid do this...

1) Buy a few cheap USB Thumb drives...and buy a cheap digital camera on eBay

2) Download and verify the hash of Ubuntu Live CD and put it on the USB drive. After its done flashing, open the USB drive in Windows and add the Electrum ( make sure to verify hash) software along with any dependency.

Basically follow
https://gist.github.com/jacoblyles/80898d6388880334f3e5a78785702ccc

3) Make your new wallet offline  and memorize the 12 words. You will need to get the Master Public Key on your online PC. Basically view the QR Code and take a photo with your iPhone

4) On your online computer, install electrum, and install zbar (QR program), and read the QR image on your iPhone. And load that Public Key as a watching address

5) When you want to spend, insert your Ubuntu live CD and follow those steps in the (2) point to recreate your old wallet. You create a unsigned transaction in Windows (online PC) and take a photo with your cheap digital camera on eBay. Then you take out your flash card out of your digital camera and put it into the offline PC. This way the digital camera is never connected to the online computer.

6) Read the QR code with zbar on Ubuntu and open Electrum and recreate your wallet with your memorized 12 words (not that hard to remember) and when the wallet is created, you sign the transaction and view QR code of the signed transaction and take a photo with your iPhone and bring that back to your Windows computer as before. Then you just broadcast the transaction.

Probably skipped a few steps but this is the best way to keep your BTC safe and essentially barring any future Electrum bugs or Brain damage, your coins are 100% safe.
legendary
Activity: 3472
Merit: 10611
September 05, 2018, 11:17:42 PM
#5
you don't hold coins in your wallet, you hold keys in your wallet. your "coins" which are transaction outputs are stored on the blockchain aka the distributed ledger held by the bitcoin full nodes. to know your balance you need to check this "blockchain" and see what is the final balance after all the "coins" have come in and went out. which means you either have to have the whole thing which is more than 1GB or you have to connect to the internet and check your balance by using a node that has it, it can be a block explorer node or an SPV wallet connecting to a node.

as for spending your wallet is only responsible for storing the keys and using them to cryptographically prove those coins you are spending belong to you by signing the transaction. a transaction which you can create elsewhere (on another PC connected to the internet) and only sign it offline. then you send it to the network for miners to put in a block and finalize the transfer of coins.

Get a flash drive, copy an Electrum installer/stand-alone executable and the Electrum data directory
[C:\Users\(Your_Username)\AppData\Roaming\Electrum\wallets] for Windows.
Paste it in the same directory of your Laptop's drive, then install the installer or Store the stand-alone executable.
This will create a "clone" of your whole Electrum from the online PC which includes the transaction history and settings.
Now, delete the standard wallet from the online PC and create a watch-only wallet based from its extended/master public key.

this is not a good idea under any circumstances because if you do this you have NOT created a cold storage. you only transferred a wallet you had to another PC which might as well have been compromised. not to mention that blockchain is a changing thing that is moving forward constantly if you just copy things now they become obsolete in a couple of minutes. after a couple of days or after spending or receiving funds you will be left with a wallet that will always show you the same balance while your balance had changed a long time ago. and you can't just keep copying things to your cold storage and risk contaminating it.


the link you included after this is a good one.
legendary
Activity: 2618
Merit: 6452
Self-proclaimed Genius
September 05, 2018, 10:05:51 PM
#4
Says video does not exsist
Just follow this:
Get a flash drive, copy an Electrum installer/stand-alone executable and the Electrum data directory
[C:\Users\(Your_Username)\AppData\Roaming\Electrum\wallets] for Windows.
Paste it in the same directory of your Laptop's drive, then install the installer or Store the stand-alone executable.
This will create a "clone" of your whole Electrum from the online PC which includes the transaction history and settings.
Now, delete the standard wallet from the online PC and create a watch-only wallet based from its extended/master public key.

Works just fine to me, but there's a "safer" way to do this:
http://docs.electrum.org/en/latest/coldstorage.html

will the program tell me my balance or do I need to keep track of it? Thanks for your help
No, but everytime you import, sign and save an unsigned tx, it will be saved in the history and will deduct the transaction's inputs from the last known balance of the wallet displayed as a local transaction.
newbie
Activity: 9
Merit: 0
September 05, 2018, 01:57:07 PM
#3
Says video does not exsist
legendary
Activity: 2758
Merit: 6830
September 05, 2018, 01:48:07 PM
#2
Check this video: https://youtube.com/watch?v=DQumISxkJs
It shows how to use an online and offline PC to create, fund and spend coins with a cold storage wallet.
newbie
Activity: 9
Merit: 0
September 05, 2018, 01:36:51 PM
#1
Hello all,

I am new to this, I have an Electrum wallet with bitcoins, I want to do cold storage, I have an old laptop with no network card and no access to the internet, my questions are, how do I move my coins from my current wallet to cold storage wallet? Since the cold wallet never connects to the internet. will the program tell me my balance or do I need to keep track of it? Thanks for your help

Dean
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