Questions tagged [privacy]

Questions related to data and smart contract privacy. For questions related to user anonymity, use the [anonymity] tag.

Filter by
Sorted by
Tagged with
0
votes
1answer
87 views

User anonymity while submitting data in smart contract

I've written a smart contract, that is a crowd sensing system. Where post posting a task user view that task and if they have what I'm asking for/and meet the task requirements they submit certain ...
2
votes
1answer
62 views

Save temporarily-shareable private data using Quorum

Can we use Quorum (or any other Ethererum variation) to save private data that can be shared with other parties for a temp period? The use case is that: A patient can share his medical data that is ...
0
votes
2answers
351 views

Which wallets lets you generate multiple ethereum addresses?

Is there a wallet that lets you generate multiple ethereum wallet addresses? I don't like the fact that I only use one address and that everyone can see what I have. Or are there other ways to keep ...
1
vote
1answer
127 views

Data privacy with block chain in health care?

I'm new to the concept of block chain and have only been reading about it the past four hours. I hear a lot of marketing and business folks tell me that block chain is the way of the future for data ...
0
votes
1answer
213 views

How do private members work?

The solidity documentation says that Everything that is inside a contract is visible to all external observers. Making something private only prevents other contracts from accessing and ...
1
vote
1answer
93 views

Enigma “secret contract” and concealing transactions history: How is it possible?

Enigma protocol is a second-layer, off-chain network that aims to solve privacy issues in blockchain. However In Enigma blog, there is an article (Link to Article), explaining the secret contract, ...
2
votes
2answers
79 views

How to listen to inter-node communications regarding transactions

If I run a full node (say geth) in the Ethereum network, then the way things work out is that every node releases/ announces new transactions as they receive new ones. I'm assuming that my node must ...
1
vote
1answer
77 views

Hiding values from calculation (zkSnarks?)

In reference to a calculation of a hidden stored value. For example: Account A & Account B Both have hidden stored values. Accounts A cannot know B's hidden stored value, and vice versa. Is ...
0
votes
2answers
45 views

Privacy concern

I have a smart contract where user submit data based on a task set by the owner, post doing so the owner in another contract offers this data to the highest bidder. Is it possible to ensure the ...
1
vote
1answer
104 views

ENS Domains and new receive addresses for privacy

Currently I use a new receive addresses every time I receive ETH - Ledger Live creates new receive addresses by default when an address has been 'used' as this is good practice in terms of privacy. ...
3
votes
1answer
43 views

What mathematical concepts do I need to master in order to understand the Aztec Procotol?

What mathematical concepts do I need to master in order to understand how privacy in the Aztec Protocol works? When I look at the white paper, I have no idea what is going on; however, I am confident ...
3
votes
1answer
244 views

zk-SNARK use cases in blockchain (except payment)?

Is there other examples of using zk-SNARK for supporting "private transactions" except Zerocoin or Zchach ? (For example, is it possible to use zk-SNARK for health data ? or any other use cases in ...
21
votes
3answers
3k views

Private info in an Ethereum smart contract

Is there any way to store info on a smart contract, and keep it a secret? If a contract has a state variable that is not public like: contract foo{ uint public publicVariable; uint notPublic;...
2
votes
1answer
27 views

See what's inside an ethereum transaction

If someone sends a transaction to the network, let's say they execute the transfer function on a solidity contract, is there any way for someone to see their interaction with the contract? Meaning the ...
0
votes
0answers
14 views

Is it necessary to have one Orion node per Eth node? Can I have multiple Eth nodes connected to one Orion node?

I would like to know if it is possible to connect multiples nodes to one Orion node.
0
votes
2answers
171 views

Quorum private transactions not private

I am struggling to enforce privacy using Quorum's privateFor option. I have provisioned a consortium in Azure blockchian service with 3 nodes. I deploy a smart contract from node2 privateFor node1 ...
3
votes
2answers
256 views

How is authorization handled in smart contracts

I have deployed a Quorum network on Azure Block chain service to be used by specific invited members of a consortium. I have not yet explored the privacy features provided by Quorum on top of Ethereum....
1
vote
1answer
87 views

How to hide data and reveal it in a smart contract

I know the topic has already been discussed but I did not find any satisfying answer. Do you know a way to put some private data in the blockchain and release / reveal it to a designated personn. I ...
5
votes
2answers
589 views

Ethereum facilitation for zk-SNARKs

There has been a lot of talk about leveraging zk-SNARKs to bring privacy features to the Ethereum Blockchain. My question is, how is Ethereum facilitating the verification of zk-SNARKs at the moment, ...
22
votes
2answers
2k views

What are effective techniques to encrypt/decrypt data stored in a smart contract?

Rather than sending and storing plain text in a smart contract, the use case objective is to encrypt first and then subsequently access the data and decrypt at the point of use. What is the most ...
0
votes
0answers
65 views

Is there a tool to obfuscate my transactions history by funneling it through a bunch of addresses I control?

I occasionally gift ETH to friends and family and I'd like a bit of financial privacy after gifting them. I understand this method is not fool proof to find out the source of funds, but at least it ...
0
votes
0answers
22 views

Can a dapp/smart contract execute a transaction based on a private github file modification?

Scenario Suppose someone promises to deliver code to a private repository, that person is so sure they will, that they even said: "here is x eth, if I don't deliver in time, send the x eth to a ...
0
votes
2answers
68 views

Auction contract privacy

I have an auction contract, where bidders bid with Ether then me (owner) select which offer is most suitable and thus this bidder is contract winner. Once the winner is selected, I send him data as a ...
3
votes
2answers
217 views

Confidential value transfers

Is there currently any way to do confidential transactions with Ethereum for a custom token? If not, is there any work/research being done on how this might be possible?
0
votes
1answer
38 views

Data integrity and privacy [closed]

I have a crowd sensing system where user after checking the task I provide for a location x, sends temperature values to the contract of that location. I've been trying to a way to implement data ...
13
votes
4answers
1k views

With a ring signature mixer, will Ethereum transactions be completely anonymous?

I was reading the Serenity PoC2. The part quoted below grabbed my attention. Does it imply full anonymity for Ethereum transactions should I decide to use the ring signature mixer? Ring signature ...
0
votes
1answer
29 views

How does Ethereum ensure that “users can own their data, and your apps don’t spy and steal from you”? [closed]

What features in ehtereum would ensure that the Dapp would never spy on you or steal your data?
2
votes
2answers
1k views

Issue with New version of Metamask: Remix cannot detect the Metamask address

I have just installed Metamask version: 6.3.1 Now in Remix, the address of my account in metamask is not detected. The account box in remix remains always blank now (see picture below). Note that I ...
32
votes
3answers
6k views

zk-SNARKs vs. Zk-STARKs vs. BulletProofs? (Updated)

zk-SNARKs, Zk-STARKs and BulletProofs are three major zero knowledge proofs to provide privacy for the blockchain technology. If we can compare them, (1) Bulletproofs and Zk-STARKs require no ...
8
votes
2answers
400 views

When a smart contract is deployed, is its source code publicly viewable?

When a smart contract is deployed to the blockchain, is the source code then publicly viewable to all participants? For example, what you see here in Etherchain. I am aware that there are some ...
1
vote
1answer
55 views

How would zkSNARKs reduce computation on Ethereum mainnet?

cmiiw, zkSNARKs mean that computations can be verified by a single node and therefore not executed by every node on the network-- link, and work is being done to include this feature in the mainnet. ...
1
vote
0answers
33 views

What are the drawbacks of layer 2?

The scalability trilemma states that a blockchain can only have two out the following three properties: decentralization, scalability, and security. Layer 2 protocols aim to make Ethereum more ...
2
votes
3answers
1k views

Confidentiality in Blockchain

Can Blockchain miners see confidential transaction information? Since they have the public key, they decrypt the transaction for the purpose of verification. So if I am mining in Ethereum, I can tweak ...
1
vote
1answer
406 views

ZK-SNARKS with ZoKrates - problems with proving the hash preimage tutorial

Just noticed today that ZoKrates has finally support for SHA256! I wanted to see it in action, so I followed the tutorial at https://zokrates.github.io/sha256example.html with a slight modification of ...
7
votes
2answers
190 views

Is it safe to commit truffle build files to Github (open source)?

Regarding the json build files that Truffle produces based off of my smart contract, is it safe for this information to be treated as public? I just want to be sure it doesn't contain any sensitive ...
2
votes
4answers
272 views

Is it possible to obscure the owner of a non-fungible token?

Basically, I'd like to have unique records which can be transferred between parties without anyone knowing who owns a particular record until a transfer occurs, at which time only the recipient can ...
6
votes
2answers
626 views

Updated: Is it possible to hide the sender or receiver of transactions by “zk-SNARK” or “Bulletproofs”?

To support the user privacy, is it possible to hide the sender address or receiver address of transactions by "zk-SNARK" or "Bulletproofs" ? Or we’ll be able only to hide the value that is mapped to ...
2
votes
1answer
53 views

Masking Ethereum Address in a transaction [duplicate]

I want to hide the ethereum addresses of dApp users so that your transactions will not be traced by one who you have interaction earlier. The use case is actually similar to the application: Alice ...
1
vote
1answer
60 views

Parameter's Value visibility

Is the value of a contract's method's parameter visible on blockchain? On Etherscan, in the tx information there is an Input Data field, which details says The binary data that formed the input of ...
2
votes
1answer
450 views

How privacy can be ensured in smart-contracts?

When a smart-contract is created following an agreement between two entities, how the state of that contract (data) can be kept secret to only the two contractors? I heard about Quorum, but how ...
0
votes
1answer
175 views

Is data inputted as a parameter for a smart contract function visible?

Let's say I have something like this: bytes32 person; function registerPerson(address _person) public { bytes32 x; x = sha256(abi.encodePacked(_person)); person = x; } For privacy reasons, ...
0
votes
1answer
51 views

Implementation of privacy in blockchain

How can we see transactions in a particular block of Bitcoin, if they are encrypted and only Merkle root of transactions is stored on the blockchain. I think in that way we should be having an ...
11
votes
3answers
5k views

Is there any way to hide a transaction?

Is there any way to hide a transaction on the Ethereum blockchain? Some blockchain have protocols that implement this by default, like Monero and Zcash. Is something similar possible on Ethereum?
9
votes
1answer
655 views

What data will zk-SNARKs protect?

Implementing zk-SNARKs is planned in Ethereum roadmap, what data will be obfuscated? transaction sender and receiver? data in transactions? data stored in contracts? variables and methods in ...
1
vote
2answers
52 views

Is there any way to fund a new account privately via a randomising pool?

It isn't currently possible to create a new HD wallet account and privately fund it, is it? I'm aware of this thread, but I'm not asking about SNARKs. Instead, I'm curious if there's any way to send ...
0
votes
1answer
97 views

Privacy-preserving smart contracts: examples, tutorial, best practices?

I want to make a proof-of-concept about privacy-preserving smart contracts. I know it's uneconomical to use encryption with Ethereum smart contracts. Are there best practices about how to do that? ...
2
votes
1answer
873 views

An example on using “zk-SNARK” in “smart contract”?

I read this article: https://media.consensys.net/introduction-to-zksnarks-with-examples-3283b554fc3b However, it's not clear to me a function such as zksnarkverify has been already implemented in ...
1
vote
2answers
292 views

Is data stored in string form in smart contracts publicly readable?

As a beginner, I wrote the contract below for learning purposes, aiming to create a "Safe Messaging System": pragma solidity ^0.4.24; contract SafeMessage { string message; string password; string ...
1
vote
1answer
312 views

Quorum privateFor visibility

Our current project requires that the recipients of a private transaction are unknown to the rest of the network. So my question is: is the privateFor field dropped before sending the transaction to ...
3
votes
1answer
78 views

How to use key derivation and 'coin selection' to increase privacy, like in Bitcoin?

In Bitcoin, you can have increased privacy by never re-using addresses. A single private key can generate many addresses if you are using a key derivation scheme. In Ethereum, instead of UTXOs you ...