15
votes
Is there any Ether mixer / tumbler available?
Philip Kirkbride's answer is misinterpreting cryptographers' use of obfuscation, and is also wrong. Mixers cannot be 'decoded' with any feasible amount of computing power. 'Decoding' the input-output ...
- 1,099
11
votes
Is there any way to hide a transaction?
No.
All information on the blockchain is visible to all participants.
Having said that, some clever uses of encrypted data exist for specific use cases. zkSnarks may provide general-purpose ...
- 55.6k
6
votes
Accepted
How to use the zksnarks capability of Ethereum?
A full answer would take a lot of time and space, and the general situation right now is that there's no easy way to use the zkSNARK precompiles.
The general outline are as follows:
Construct a ...
- 37.3k
5
votes
Is there any way to hide a transaction?
There's ring mixing contract with source code here which has similar (in fact, flipped) properties to Monero's ring signature mixes.
It offers anonymity to recipients rather than senders, meaning ...
- 1,099
5
votes
With a ring signature mixer, will Ethereum transactions be completely anonymous?
The property of anonymity offered by ring signature mixers is more like what you would intuitively think of as 'plausible deniability', or 'anonymity with respect to an anonymity set'.
The actual ...
- 1,099
4
votes
How are some addresses known to belong to certain exchanges?
As @RobHitchens states, Etherscan maintains an address book. To populate the address book, Etherscan can do some sleuthing to figure things out (after all, Ethereum is only pseudonymous) and they have ...
- 6,680
4
votes
Is there any way to hide a transaction?
Sort of.
There's some work going to get zCash running on ethereum here: https://z.cash/blog/zksnarks-in-ethereum.html.
It seems like the ideas is: you would probably have an initial, traceable ...
- 161
4
votes
Is it possible to obscure the owner of a non-fungible token?
If your NFT is ERC721 compliant, then no, according to the non-finalised ERC721 Standard, this is not possible. A requirement of the standard is that your NFT token contract contain the following ...
- 3,585
4
votes
Accepted
Is it logical to use "Proof-of-Authority" for a "public" blockchain?
According white papaper of bitcoin -
In Bitcoin or for any public blockchain privacy is maintained by not exposing which public key is associated to which user. So users can participate in the ...
- 2,577
3
votes
Accepted
How to implement Ethereum mixing (or coin tumbling) to preserve anonymity in smart contracts?
The problem with mixing is that you need a way for the user to signal to the contract (or to the contract owner) the address they want to receive the ETH at after it is mixed.
If you have a trusted ...
- 46
2
votes
Can variables be read by miners?
Yes, anyone on the network can read the storage contents allocated to any given account so you must not assume the data is private, even if the variable you use is marked as private in Solidity.
- 1,171
2
votes
Can variables be read by miners?
In other words, who can see the addresses in the array?
Anyone. The data in the ethereum blockchain is public.
I supose there is only way to store data that must be private is encryption.
- 940
2
votes
Is it possible to obscure the owner of a non-fungible token?
To add to @anAllergyToAnalogy's answer.
Even if your token is not ERC721 compliant you are basically asking whether it's possible to store secret information in the blockchain. You probably know that ...
- 30.2k
2
votes
Blockchain use case – Trying to understand provenance tracking
I'll try an admittedly over-simplified summary and see if it helps.
Just as a database isn't merely a better spreadsheet, blockchain isn't merely a better database. In fact, in many respects, ...
- 55.6k
2
votes
Is there any anonymity in Proof-of-Authority?
Your assumption is not true.
Naturally you can give somebody, who you do not know, technical permission to run proof-of-authority node in your network. There is nothing technical preventing it. You ...
- 23k
2
votes
Accepted
Anonymity preserving approaches in smart contracts?
As mentioned in the comments, Ethereum does not support UTXO like Bitcoin does. So Ethereum has always one input and one output.
Just to make sure what I mean here with Ethereum mixing (sometimes ...
- 30.2k
2
votes
Accepted
Is there any way to fund a new account privately via a randomising pool?
You could do exactly this with ZKSnarks but the overhead would be that you would have to actually remember/track a certain amount of information.
By privately fund it, I take it, making private the ...
- 1,960
2
votes
Is there any way to fund a new account privately via a randomising pool?
The only practical possibility to pass trough a serious forensic investigation on blockchain without revealing where are funds coming and going is by means of a off-chain server. I mean on Ethereum ...
- 3,194
2
votes
Decentralized exchange that lets you cash out Ether for fiat money?
First, if you want to exchange crypto for fiat it's not possible to do this in a decentralized way. If your concern is KYC then some options are more private than others.
There is always the option of ...
- 121
1
vote
can an ipfs node identify a partner in file transfer?
IPFS is not a place you upload files to, it's a network you're part of.
IPFS is a peer-to-peer system, comparable to bittorrent. You are a peer, and you host files so that other peers can download ...
- 4,308
1
vote
Decentralized exchange that lets you cash out Ether for fiat money?
You can try localcryptos.com, which is a non-custodial crypto marketplace where people buy and sell crypto on their own terms, using any payment method (so it's a kind of peer-to-peer marketplace).
- 3,409
1
vote
Using NFT paired to credentials for identity verification
Rather than using credentials or an NFT, maybe just have the user interact with your application through their ethereum address / wallet. Any changes to this address's account in your application ...
- 1,481
1
vote
Data integrity and privacy
I'd like ensure the integrity of the data sent in the sense that the user is actually in that location and not just faking the location
This is outright impossible. You need to trust the data coming ...
- 23k
1
vote
Auction contract privacy
We've been working on enabling truly private auctions. You still need to add some type of tx privacy to conceal the bids permanently, but you can do private auctions (without commit reveal) using ...
1
vote
User anonymity while submitting data in smart contract
I don't think that is doable because every action that changes the state of the blockchain needs to know the address of the sender to make a transaction and that transaction is public for everybody.
...
- 1,144
1
vote
Is it possible to obscure the owner of a non-fungible token?
zknifty is a working example of non-fungible tokens (NFTs) based on zk-SNARK proofs. However, it was not designed for privacy as its goal is to "compress" several transactions into one proof (i.e. it ...
- 130
1
vote
How to make a token private
You can try using zeth which is an implementation of the zerocoin protocol in an ethereum smart contract (https://github.com/zcoinofficial/zeth/blob/master/contracts/Zerocoin.sol) which you could ...
- 1,593
1
vote
Accepted
Tracing wallet IP address
Yes. An attack on Ethereum of this nature can be executed in the exact same way.
- 6,680
1
vote
Accepted
ENS: Guessing bids amounts and protecting bid anonymity
How would one go about guessing the bid amount given the .eth name?
If you know which bid transaction is related to the name in question (maybe the account only sent one bid, and you know its name), ...
- 6,411
1
vote
Is there any Ether mixer / tumbler available?
tornado.cash is a mixer that has received a fair amount of attention. As the site states, it has been audited, but is still considered experimental. I'm not knowledgeable enough to comment on what it ...
- 2,784
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