18
votes
Accepted
Is it safe to reuse a Bitcoin address?
There are both security and privacy related issues that arise from address reuse. Based upon your question you are less concerned with the privacy implications and more concerned with the security ...
- 2,680
12
votes
Accepted
Why is the change address for a transaction the same as the originator address?
Many wallets let you control where to send the change. In most cases it is advisable to send to a new address to reduce traceability and increase your privacy a little, but not everyone does and ...
11
votes
Why is the ledger public?
When Bitcoin was invented, Blockchain analysis was not as advanced as it was today and pseudonymous transactions were believed to be closer to anonymous than they are with Bitcoin today. Under the ...
- 386
9
votes
Accepted
How does not practicing address reuse hurt my privacy?
There's a bigger attack surface for someone that wants to doxx you. They only need to link a single transaction to your real life person to know all the transactions you've participated in. A single ...
- 7,749
7
votes
Accepted
Why do wallets use multiple private keys instead of one each?
Why is that so, don't you only need 1 private key to hold all bitcoins and manage them?
Sure you could use only one private key and its associated address, but that is not recommended. It is more ...
- 68.5k
7
votes
How do Reusable Payment Codes work?
The gist of the reusable payment code BIP is that you can gain some measure of address privacy by combining BIP32 (hierarchical deterministic wallets) with Diffie-Hellman key exchange. To understand ...
- 7,749
7
votes
Is it safe to reuse a Bitcoin address?
Why address reuse is discouraged:
Reduced security An unused address is protected by ECDSA AND several SHA-256 and RIPEMD-160 operations, but only ECDSA after being used because the public key must ...
- 1,410
7
votes
Would reusing addresses result in a lower fee?
Addresses do not exist at the protocol level. You'll pay exactly the same fee whether you used the same or different addresses to withdraw. What matters is that there are many outputs you have to ...
- 102k
7
votes
What are the advantages/disadvantages to using the same Wallet Address?
Questions about altcoins are off-topic here, but the answer is essentially universal: if you re-use addresses, especially because of a desire to think of them as a long-term identity, you're ...
- 102k
6
votes
Can I receive Bitcoin on any of my wallet addresses?
Yes! With an HD (Hierarchical Deterministic) wallet you control all the addresses inside of it. Using a new address for each transaction is actually a good thing for privacy.
https://en.bitcoin.it/...
5
votes
Why is the ledger public?
The ledger has to be public in order for Bitcoin to be decentralized. The designers of Bitcoin didn't want to need anyone to play the role of a "bank" who keeps all the records, and whom everyone ...
- 23k
5
votes
Sending from same address multiple times VS receiving to the same address multiple times
This is a weird question because you have to send from the address you receive from. If you receive all your bitcoin to the same address, you will inevitably be spending from that same address as ...
- 8,822
5
votes
Accepted
If the bitcoin address changes every time, why there is more than one transaction for an address in the ledger?
You need to differentiate between the website's wallet (Blockchain.info-wallet) and the blockchain itself.
You are allowed (by the bitcoin protocol) to make as many transactions per adress as you ...
- 2,117
5
votes
Accepted
Is there a way to generate new addresses for someone else's wallet?
Bob can provide Alice with an extended public key (xpub). This will allow Alice to generate as many addresses as required, all of which will be accessible to Bob via the corresponding extended private ...
- 16.9k
5
votes
If I reuse the same address can a previously used transaction be reused?
Can somebody take the transaction tx0 I signed and publish it in order to spend the new coins with the old transaction?
No.
Firstly, the transaction inputs are already known to have been used. Any ...
- 25.1k
5
votes
How many wallets don't support address reuse? (for refunds)
I think it would be helpful for you to identify your service here, so that I can encourage people to not do business with you.
Users generally have no idea if this will work safely or not, so a ...
- 7,696
5
votes
Accepted
Re-use change address as a receive address
Technically speaking, is it possible to reuse a change address from a previous transaction and make it a receive address?
Technically that would be possible. The network rules have no concept of ...
- 102k
4
votes
Accepted
Static receive address instead of dynamic?
You can certainly give out the same address to as many people as you want. An address is really just a representation of the public part of a cryptographic key pair, and you will still have the ...
- 8,822
4
votes
I accidentally sent bitcoins twice to the same address
It is not clear what exactly happened.
If you've made two subsequent transactions to the same address that should not be a problem. Addresses can be used more than once to receive money.
If you ...
- 72.6k
4
votes
Accepted
Why do transactions send coins to the same address as they spent it from?
Likely the sender didn't have an unspent output that had exactly the amount he wanted to send. So he choose an unspent output that had enough and sent the remainder back to himself.
Accounts do not ...
- 51.4k
4
votes
Sending from same address multiple times VS receiving to the same address multiple times
You can receive as much as you want to an address, but you should spend from that address only once.
The reason you want to spend from an address only once is that this exposes your ECDSA public key ...
- 7,749
4
votes
Why is the change address for a transaction the same as the originator address?
Bitcoin Core sends change to a different address, but the Bitcoin protocol does not require that. You can write a Bitcoin client that sends the change to the original address.
There's no benefit to ...
- 29.3k
4
votes
Security implications of regular saving into cold storage
Q1: Depens on how you use it.
Transactions to an address does not decrease it's security.
Using a cold-storage wallet and taking it online exposes your wallet and it's security.
Q2: It's correct. ...
- 163
4
votes
Accepted
Are all UTXOs locked by an address spent in a transaction?
Transactions explicitly refer to which UTXOs they are spending.
You can construct a transaction which only spends one of the two 5-BTC UTXOs, and sends 2 BTC to the destination and 3 BTC to a (...
- 102k
4
votes
Why is it a privacy problem to always pay to the same address?
Assume you are using a unique common address for each customer and at the end of the day/week/month you make payments to your employees, suppliers or partners. When making those payments, if those ...
- 7,348
4
votes
Accepted
Why do self-loops exist in the bitcoin transaction graph?
You are looking at transactions the wrong way. Bitcoin does not actually use addresses and their balances. The protocol has no concept of what an address is, nor does it need to. It also has no idea ...
- 68.5k
4
votes
Accepted
Address Reuse vs. Coin Selection
Do the instructions to not reuse an address include change? That is, should I generate a new key pair for any transaction that needs to receive change, and then manually specify my change be sent to ...
- 102k
4
votes
What are the advantages/disadvantages to using the same Wallet Address?
Gap Limits
I want to just smash the button until I find an address with some aesthetic/memorable strings. But I have no idea if this is a bad idea, wastes resources,
That could create problems when ...
- 25.1k
3
votes
Accepted
Does address-reuse make Bitcoin private keys vulnerable to quantum computing?
The simple explanation is that the attacks that quantum computing enables require information (the public key) that isn't available until after the first transaction is seen.
Until the first ...
- 88
3
votes
Accepted
How or why "a Bitcoin address is a single-use token"?
The bitcoin addresses are permanent addresses. You can re-use the addresses if you want. But when reusing it causes privacy issue as any one will be able to find out the number of transactions or the ...
- 758
Only top scored, non community-wiki answers of a minimum length are eligible