How do offline addresses get known by the Blockchain?

[lomalio]

So I have heard that for security purposes it is better to make a new wallet when offline. I.e. create the wallet when not online. Then send the coins to it. How is this supposed to work? If the wallet (.dat etc) is removed from the system and put into a USB stick then how does the Blockchain ever know the public address?

[Dare]

The blockchain first sees addresses when coins are sent to them, there isn't a separate discovery process for addresses. You can send coins to any valid address, even ones without a known private key such as 1BitcoinEaterAddressDontSendf59kuE.

[lomalio]

In that case, why are people not using meaningful names for addresses?

[Dare]

In that case, why are people not using meaningful names for addresses?

Because generating vanity addresses is computationally expensive. With a sufficiently powerful computer, finding one with a few specific letters (e.g. an address starting with 1Wolf) takes seconds, but specifying a longer prefix (e.g. 1WolfRUGDx1) takes exponentially longer unless you're very lucky, like I was for that one while searching for a 1Wolf address. If you want to generate your own vanity addresses, look into vanitygen for CPU mining and oclvanitygen for mining on AMD graphics cards. You can also pay someone to find an address for you with split-key address generation (so they never control the private key) either here on the forum or through the vanity address pool[url].

[dbshck]

In that case, why are people not using meaningful names for addresses?

Because it's very hard to generate such vanity address + it's private key

The address you seen above is valid, meaning you can send bitcoin to them. But nobody can't spend coin FROM that address since nobody has it's private key.
So the coins that has been sent to that address is kinda like stucked forever.

[MakeBelieve]

Yeah it only gets stored when a payment is made otherwise it will just show 0 Bitcoin.

[Lieji]

In that case, why are people not using meaningful names for addresses?

With a private key, you can easily calculate the associated bitcoin address.
But with a bitcoin address, there is no way to find out the associated private key.

So, in order to create a special vanity address (eg. starting with 1bitcoin), you need a software (eg. Vanitygen) to do the following 3 steps:
1. Create a new private key.
2. Check if the associated bitcoin address matches the pattern (in this case, starting with 1bitcoin)
3. If yes, stop; if not, go back to step 1.

The longer the pattern, the more time and computation power you need on average.

[BitcoinBarrel]

Think of it this way... ALL of the Bitcoin Addresses and Private Keys already exist.

So technically, Bitcoin Addresses are not generated Offline because they exist in the pool of possible addresses.

SHA256 algorithm can be used on a computer that is not connected to the internet. When you apply the SHA256 algorithm to any value then you end up with a Private Key. You can find the corresponding Bitcoin Address and write the private key down on a piece of paper. Since the computer was never connected to the internet then the address was "generated offline".

From there you can receive payments to the Bitcoin Address, but unless you import the private key into an online wallet like Blockchain.info or the Bitcoin client, then you will not be able to spend the coins.

[apepoof]

On topic of vanitygen there are a lot of scammers out there and your private key may be compromised. Best avoided imo.

[Bitsaurus]

On topic of vanitygen there are a lot of scammers out there and your private key may be compromised. Best avoided imo.

Thank you for pointing this out.

If you have somebody make a vanity address, like one for me might be 1Bitsaurus..... , you need to be aware of the fact that they will have access to your private key and can potentially take the coins sent to that address at any time.  There are solutions to this but you must read up it.  Also assume the person generating the address for you is a crook unless they have some well establish history of being trustworthy.

[ncsupanda]

On topic of vanitygen there are a lot of scammers out there and your private key may be compromised. Best avoided imo.

Thank you for pointing this out.

If you have somebody make a vanity address, like one for me might be 1Bitsaurus..... , you need to be aware of the fact that they will have access to your private key and can potentially take the coins sent to that address at any time.  There are solutions to this but you must read up it.  Also assume the person generating the address for you is a crook unless they have some well establish history of being trustworthy.

This is mentioned further up, and is referred to as split key generation - just for people who stumble here, split key generation means that whoever generates the vanity address for you does not own the private key.

It's safe - just needs a middleman. Which is great.

[5 Guys Burgers]

On topic of vanitygen there are a lot of scammers out there and your private key may be compromised. Best avoided imo.

Thank you for pointing this out.

If you have somebody make a vanity address, like one for me might be 1Bitsaurus..... , you need to be aware of the fact that they will have access to your private key and can potentially take the coins sent to that address at any time.  There are solutions to this but you must read up it.  Also assume the person generating the address for you is a crook unless they have some well establish history of being trustworthy.

If I download my own program to generate my own private key, lets say i want to make it 5GuysBurgers0e9fj30fja0f blah blah blah ETC...

So I have a decent computer, 2nd fastest i7 processor at the time(from about 2 years ago) and I have a HD 6870 graphics card.

Do you think that is decent enough to make my own vanity address from a program and if so what program? Like are we talking 2 hours to make one address with what I got or 20 hours or days and days? I am trying to get a feel for if this makes any sense or not. If I make my own I assume I do not risk any private keys??

[ncsupanda]

On topic of vanitygen there are a lot of scammers out there and your private key may be compromised. Best avoided imo.

Thank you for pointing this out.

If you have somebody make a vanity address, like one for me might be 1Bitsaurus..... , you need to be aware of the fact that they will have access to your private key and can potentially take the coins sent to that address at any time.  There are solutions to this but you must read up it.  Also assume the person generating the address for you is a crook unless they have some well establish history of being trustworthy.

If I download my own program to generate my own private key, lets say i want to make it 5GuysBurgers0e9fj30fja0f blah blah blah ETC...

So I have a decent computer, 2nd fastest i7 processor at the time(from about 2 years ago) and I have a HD 6870 graphics card.

Do you think that is decent enough to make my own vanity address from a program and if so what program? Like are we talking 2 hours to make one address with what I got or 20 hours or days and days? I am trying to get a feel for if this makes any sense or not. If I make my own I assume I do not risk any private keys??

The time it takes is completely dependent on the number of characters i.e. complexity.

I created one with 1Pandas and it took 2 hours with a 4 GHz i7.

[Lieji]

On topic of vanitygen there are a lot of scammers out there and your private key may be compromised. Best avoided imo.

Thank you for pointing this out.

If you have somebody make a vanity address, like one for me might be 1Bitsaurus..... , you need to be aware of the fact that they will have access to your private key and can potentially take the coins sent to that address at any time.  There are solutions to this but you must read up it.  Also assume the person generating the address for you is a crook unless they have some well establish history of being trustworthy.

If I download my own program to generate my own private key, lets say i want to make it 5GuysBurgers0e9fj30fja0f blah blah blah ETC...

So I have a decent computer, 2nd fastest i7 processor at the time(from about 2 years ago) and I have a HD 6870 graphics card.

Do you think that is decent enough to make my own vanity address from a program and if so what program? Like are we talking 2 hours to make one address with what I got or 20 hours or days and days? I am trying to get a feel for if this makes any sense or not. If I make my own I assume I do not risk any private keys??

The time it takes is completely dependent on the number of characters i.e. complexity.

I created one with 1Pandas and it took 2 hours with a 4 GHz i7.

Since bitcoin address is encoded in base58, an additional character will make the difficulty of finding the vanity address 58x harder (ie. expected time 58x longer).

[Rannasha]

On topic of vanitygen there are a lot of scammers out there and your private key may be compromised. Best avoided imo.

Thank you for pointing this out.

If you have somebody make a vanity address, like one for me might be 1Bitsaurus..... , you need to be aware of the fact that they will have access to your private key and can potentially take the coins sent to that address at any time.  There are solutions to this but you must read up it.  Also assume the person generating the address for you is a crook unless they have some well establish history of being trustworthy.

If I download my own program to generate my own private key, lets say i want to make it 5GuysBurgers0e9fj30fja0f blah blah blah ETC...

Bitcoin addresses always start with a 1 or 3 (for multisig). Altcoins have different leading characters.

So I have a decent computer, 2nd fastest i7 processor at the time(from about 2 years ago) and I have a HD 6870 graphics card.

Do you think that is decent enough to make my own vanity address from a program and if so what program? Like are we talking 2 hours to make one address with what I got or 20 hours or days and days? I am trying to get a feel for if this makes any sense or not. If I make my own I assume I do not risk any private keys??

Time required goes up exponentially with length of the pattern. And it becomes even more lengthy if you insist on the correct capitalization. Your proposed pattern (replacing the 5 with a 1) will take many years on average (though like mining for blocks it's a luck-based process and you could get lucky and find it within seconds).

[meadefreling]

Hmmm very educative exchange of knowledge.At least now i see the reason why most times i stick to this forum to update myself.Thanks for the tutorials.

[Omikifuse]

Yeah it only gets stored when a payment is made otherwise it will just show 0 Bitcoin.

It will show a message saing that the address has never been used or the transaction still haven't been broadcasted.

0 Bitcoin balance is shown only if the address received coins but now is empty.

Of course talking about blockchain, don't know others