6

Is there a way to transfer/import bitcoin from one address to another in order to avoid transaction fees? No. It is not possible to move btc between addresses without publishing a transaction to the blockchain. However, there are some ways to accomplish a similar result (transferring/altering the ability to spend some coins), but I think every one of those ...


5

You can do this using Bitcoin Core, and it'll be even easier with Bitcoin Core 0.10's watch-only wallet support. With the current Bitcoin Core, you create a wallet on your offline machine. Using it, you get one or more addresses (saving them, for example, to a text file). You copy those addresses to your online computer and give them to people to pay you. ...


5

Payments are handled by means of an established bi-directional payment channel. While this may seem like a payment could travel in one direction to an offline participant in an open channel, in practice this would be difficult if not impossible. The problem is that a channel exists as a protocol between two active participants. There are no other ...


4

The easiest way to do this by importing the address you generated on the offline Bitcoin Core client into an online fully synced Bitcoin-Core. The command is: bitcoin-cli importaddress <address>. The benefit of importing this address into the synced Bitcoin-Core machine is that you can use it as a watch-only address which will allow you to see all the ...


4

It wouldn't be a fiat currency. fiat money: money without intrinsic value that is used as money because of government decree (N. Gregory Mankiw (2014). Principles of Economics. p. 220. ISBN 978-1-285-16592-9) No government decreed its people to use Bitcoin. Quite the contrary: One of Bitcoin's goals is to take control away from governments, whereas fiat ...


4

Armory is a popular solution for dealing with offline wallets. It is GUI based so is more user friendly than command-line / programming based solutions. https://bitcoinarmory.com/


4

You can generate a wallet for cold storage offline easily. You can then ask the exchange to use a public address of that cold storage as the recipient for a transaction. You'd still pay the fee the exchange demands to process the transaction though. Standard practice is that all trades in the exchange are just bookkeeping and are not published to the ...


3

You can simply send the signed transaction to the other entity (e.g. via Bluetooth) who then can send it to the Bitcoin network. The transaction doesn't need to be sent to the Bitcoin network by you, it just needs to somehow get to a miner to be included in a block. Even if you print it out, send someone a letter via snail mail, they type it in, and send it ...


2

I've been looking at this question too. It is my understanding that a bitcoin transaction is not "encrypted" . The information is not obscured in any way, and can be transmitted publicly without breaking the security. You are simply transmitting a "hash" of the transaction, or signature. Nothing has to be decrypted to be read. You simply verify the ...


2

Although I am not qualified enough to suggest a protocol for over-the-air, I can still get some technical pointers. You may want to ask at the ham radio SE community. Yes you can easily send Bitcoins over shortwave radio using encryption but radio encryption is not a topic of this community. It's also severely illegal in the U.S. for a HAM operator to use ...


2

electrum android app can do this! check it out, it's perfect! also seems like a nice wallet with a lot of features. your watch-only online electrum can create an unsigned transaction with QR code. your offline electron can scan then sign it & generate a QR code for you to broadcast with online electrum!


2

A watch only version of a multisig wallet must be created using the xpubs of both wallets not just the xpub of one wallet. Now there are two possibilities here: You created a wallet with one xpub and one seed. This wallet is not watch only and transactions generated by it need only be signed by the wallet whose xpub you used. You can tell if this what you ...


1

Without computers or electricity, Bitcoin would have no value and could not be used as it is entirely a digital asset. There are no such an object as a coin and thus Bitcoin cannot be put into a physical asset. The blockchain itself is what determines something is Bitcoin, and without it (because there are no computers or electricity), anything physical ...


1

How does the transfer between the payer and payee's wallet actually happen if both nodes are offline? From the paper: Because both, the payerX and the payeeY, have no on-line connection during the payment, the offline transaction τo is sent via local interfaces (e.g., Near Field Communication (NFC) or Bluetooth Low Energy (LTE)), in contrast to regular (...


1

I've recently learned about a product called Opendime. It's a USB flash drive which combines some entropy on the device with entropy fed to it to generate a key pair. After initialization, the receiving address can be read via USB, allowing for bitcoins to be loaded onto the device and verification of the current balance, but the private key is only ...


1

As explained in the referenced paper [4] "SMAPs: Short Message Authentication Protocols", the security issue is the delay-tolerant networking. Bitcoin already requires a minimum of 6, or better 8, blocks before a transaction is sufficiently secured. The trade off is between delaying the settlement and lowering the risk.


1

No, you can use your Trezor for your everyday use with a usual online computer (or even a computer that has malware). Connecting your Trezor to your computer oftenly doesn't mean it is not secure anymore / it is less secure.


1

Whether an address was generated online or offline is irrelevant. Any transaction that sends bitcoin to the address will be included in a block once it gets mined. You can check the address balance by searching for that address in a block explorer such as https://blockexplorer.com/


1

It looks like a testnet option was merged in early 2017, but I'm not sure if it was released: https://github.com/spesmilo/electrum/commit/d042d6e970389f97331e9caae196bf7a3af1e293 https://github.com/spesmilo/electrum/issues/541


1

Testnet transactions have the same format as mainnet transactions, so you can just create a raw transaction on your online testnet wallet, and get it signed by Electrum with a private key it thinks is associated with a mainnet address (the version byte is different, so the same hexadecimal private key will generate a different address on the testnet and on ...


1

The problem here is that creating a transaction requires 2 things: The utxo (unspent transaction output) set of your addresses. This is basically a record of all bitcoins sent to the addresses in your wallet.dat file. The private keys to actually sign the transaction. Generally, when you use an offline computer to store the private keys, you will be using ...


1

Not in a user-friendly way, no. Simple version Your offline Bitcoin client needs more information to identify which coins it is spending, so there needs to be some communication from the online computer to the offline computer. Typically, this is done by preparing most of the transaction on the online computer, then transferring it flash drive to the ...


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