Which privacy technique is the strongest?

[Abiky]

There are many privacy coins on the market each with their own features and approach towards privacy. I've read about various obfuscation methods such as CoinJoin, ZKPs (Zero Knowledge Proofs), RingCT, and Mimblewimble. Yet, I'm wondering which of these techniques is the strongest in terms of preserving your utmost financial privacy and anonymity.

Is it the one used by Monero (RingCT + Confidential Transactions), Zcash (ZKPs) or Grin (Mimblewimble)? Please enlighten me. A detailed overview among the strongest/weakest points of said privacy techniques would be greatly appreciated. Thanks in advance.

[vv181]

How do we define or measure the most private methods? One can obscure a transaction, but just ensuring the transaction itself ciphered would affirm it is a strong technique.

IIRC, there is a thread on Bitcointalk that compare most of the privacy-coin methods and technique, does anyone have the link? Because AFAIK, for example, as you stated, that Zcash used zero-knowledge proofs, but the subset of it was also used by Monero and Grin. So it should be noted that ZKPs, were generally used in privacy coins, specifically, Bulletproofs for Monero and Range Proofs for Grin. I don't know what specific techniques that are implemented on Zcash.

[rat4]

1. CoinJoin is simple. That makes it compatible with Bitcoin, but the weakest option.
- Amounts are visible. You can have multiple inputs and outputs, but the upper bound of tx is clear.
- Small anonymity set. People may opt out of mixing with you. Limited by transaction size.
- Interactive. You need to find people who want to mix coins with you and be online at the same time. There is software for that, though.

2. Mimblewimble. I haven't spent a sufficient time on it, so may be wrong here.
- Small anonymity set. Miners may know about txs more than parties that download the blockchain later.
- Limited transaction types.

3. RingCT is modular, and one of its components is Bulletproof a special zero-knowledge proof.
- Small anonymity set. Limited by transaction size.
- Limited transaction types.

4. Zero-knowledge proof is the strongest option, if used appropriately.
- Big anonymity set. All users and txs are there.
- Arbitrarily programmable transactions are possible, but I haven't seen projects that already implemented this.

How do we define or measure the most private methods? One can obscure a transaction, but just ensuring the transaction itself ciphered would affirm it is a strong technique.

By how much information is leaked when a tx is sent. The leak starts from the fact that a tx was sent. Probably it's impossible to conceal the tx time until we have a time machine.

[Abiky]

1. CoinJoin is simple. That makes it compatible with Bitcoin, but the weakest option.
- Amounts are visible. You can have multiple inputs and outputs, but the upper bound of tx is clear.
- Small anonymity set. People may opt out of mixing with you. Limited by transaction size.
- Interactive. You need to find people who want to mix coins with you and be online at the same time. There is software for that, though.

2. Mimblewimble. I haven't spent a sufficient time on it, so may be wrong here.
- Small anonymity set. Miners may know about txs more than parties that download the blockchain later.
- Limited transaction types.

3. RingCT is modular, and one of its components is Bulletproof a special zero-knowledge proof.
- Small anonymity set. Limited by transaction size.
- Limited transaction types.

4. Zero-knowledge proof is the strongest option, if used appropriately.
- Big anonymity set. All users and txs are there.
- Arbitrarily programmable transactions are possible, but I haven't seen projects that already implemented this.

This explains everything. Thank you very much. Based on what you've described here, does that mean Zcash has the strongest privacy technique? If that's the case, I'm surprised to see XMR being hailed as the #1 privacy coin in the world. ZEC's limited supply (21m like Bitcoin) and innovative approach to privacy/anonymity should've made it one of the most valuable crypto coins on the market today. It's very undervalued to say the least. The majority are not focused on privacy coins these days, so don't expect things to improve anytime soon.

I'm yet to see if developers will launch new privacy coins that will challenge existing ones in the future. The lack of innovation in the privacy space, tells us developers are afraid of increasing regulatory pressure. It's likely privacy coins will remain a niche forever. At least, people have a choice. As long as decentralization wins, nothing else matters.

[Joeyp]

Which is better - zero-knowledge proofs or ring confidential transactions privacy technigue ? Both do the same.
I think Monero is more easy to use, send, receive - no problem. Zcash you can only send, receive to shielded addresses, if you want privacy.

 

[vv181]

How do we define or measure the most private methods? One can obscure a transaction, but just ensuring the transaction itself ciphered would affirm it is a strong technique.

By how much information is leaked when a tx is sent. The leak starts from the fact that a tx was sent. Probably it's impossible to conceal the tx time until we have a time machine.

Well, I believe that is simply easily overruled by running their own node + Tor. Assuming the user interaction isn't directly involved with the transaction, I still do wonder about how to measure the strongest technique, solely in terms of the transaction itself. Surely there is pro and cons, as you have stated, so maybe it is just quite an incorrect question to ask.

The lack of innovation in the privacy space, tells us developers are afraid of increasing regulatory pressure. It's likely privacy coins will remain a niche forever.

That is simply a sheer bull. There is no lack of innovation in privacy spaces, and developers are not scared of regulatory pressure. Monero specifically is still openly researching financial privacy (https://www.getmonero.org/resources/research-lab/).

The lack of "innovation" is simply because privacy coins can't be easily pumped and dumped. It has real utility, so please make a distinction with the regular Web 3 project.

[rat4]

This explains everything. Thank you very much. Based on what you've described here, does that mean Zcash has the strongest privacy technique? If that's the case, I'm surprised to see XMR being hailed as the #1 privacy coin in the world. ZEC's limited supply (21m like Bitcoin) and innovative approach to privacy/anonymity should've made it one of the most valuable crypto coins on the market today. It's very undervalued to say the least. The majority are not focused on privacy coins these days, so don't expect things to improve anytime soon.

Zcash was disgusting at launch. It used a zero-knowledge proof with a trusted setup. In simple words, the people who were involved in the launch could break the protocol, if cooperated, hence the trust. I find it unacceptable for a cryptocurrency.
This is not the case nowadays, since they authored a new ZKP named halo2.

I'm yet to see if developers will launch new privacy coins that will challenge existing ones in the future. The lack of innovation in the privacy space, tells us developers are afraid of increasing regulatory pressure. It's likely privacy coins will remain a niche forever. At least, people have a choice. As long as decentralization wins, nothing else matters.

Folk are working. For example, there is a decent paper Zexe: Enabling Decentralized Private Computation that generalizes what Zcash accomplished. BTW, they also discuss regulations It was written in 2018, and they still work on a new blockchain. I currently evaluate whether to use this technique in my project.

Well, I believe that is simply easily overruled by running their own node + Tor. Assuming the user interaction isn't directly involved with the transaction, I still do wonder about how to measure the strongest technique, solely in terms of the transaction itself. Surely there is pro and cons, as you have stated, so maybe it is just quite an incorrect question to ask.

Oh, anonymization at the network level is another can of worms.
The question is correct, but in practice we may use what is practical, and not what is perfect in theory.

[Abiky]

Which is better - zero-knowledge proofs or ring confidential transactions privacy technigue ? Both do the same.
I think Monero is more easy to use, send, receive - no problem. Zcash you can only send, receive to shielded addresses, if you want privacy.

Why would Monero be much easier to use than Zcash? I'd say XMR is harder to understand than ZEC because of the way it's designed. It uses three keys instead of two used by coins like Zcash and the others (Bitcoin, Ethereum, etc). ZEC only has shielded addresses, whereas Monero has a public key/address, a spend key, and a view key. If you want someone else to view your transaction history, you'd need to share your view key to do that. Using only the public key won't suffice.

It takes quite a bit of understanding to get your way through the XMR blockchain. And it's even worse with Mimblewimble coins such as Grin, BEAM, and Litecoin (yes, Litecoin added said privacy feature some time ago). I think that's one of the reasons why privacy coins are very unpopular. At least, there are plenty of options to choose from. As long as R&D for privacy/anonymity continues, we should have nothing to worry about.

[Joeyp]

Which is better - zero-knowledge proofs or ring confidential transactions privacy technigue ? Both do the same.
I think Monero is more easy to use, send, receive - no problem. Zcash you can only send, receive to shielded addresses, if you want privacy.

Why would Monero be much easier to use than Zcash? I'd say XMR is harder to understand than ZEC because of the way it's designed. It uses three keys instead of two used by coins like Zcash and the others (Bitcoin, Ethereum, etc). ZEC only has shielded addresses, whereas Monero has a public key/address, a spend key, and a view key. If you want someone else to view your transaction history, you'd need to share your view key to do that. Using only the public key won't suffice.

It takes quite a bit of understanding to get your way through the XMR blockchain. And it's even worse with Mimblewimble coins such as Grin, BEAM, and Litecoin (yes, Litecoin added said privacy feature some time ago). I think that's one of the reasons why privacy coins are very unpopular. At least, there are plenty of options to choose from. As long as R&D for privacy/anonymity continues, we should have nothing to worry about.

If Zcash receiver have public address, what you will do in such a case, if you want the privacy. Therefore I think Monero is more easy to use, at least you can send to receiver. Three keys for Monero is for privacy reasons, so if you want the privacy, there are some harder things too.

[vv181]

One thing that is also related to privacy coins is the opt-in nature. Can we tolerate in which the private transaction within the chain itself is mixed up? Or in the case where regulatory pressure is imminent, forcing users not to activate the privacy features like what Litecoin MimbleWimble or Zcash is capable of, would it still be useful?

For example, are any of you aware of how much the ratio of regular vs MW Litecoin transactions? It also applied with Zcash of the transparent address/tx with shielded ones.

Well, I believe that is simply easily overruled by running their own node + Tor. Assuming the user interaction isn't directly involved with the transaction, I still do wonder about how to measure the strongest technique, solely in terms of the transaction itself. Surely there is pro and cons, as you have stated, so maybe it is just quite an incorrect question to ask.

Oh, anonymization at the network level is another can of worms.
The question is correct, but in practice we may use what is practical, and not what is perfect in theory.

I see. Do you know of any research that affirms/compares privacy-coins securities quality?

[rat4]

I see. Do you know of any research that affirms/compares privacy-coins securities quality?

It is not that I'm aware of such surveys. My current area of research is, how much there is room for privacy on a scalable programmable proof-of-stake blockchain, and what trade-offs to make among the four.

In addition to my first message, there is one more criterion to consider: future-proofness. Can a scientific or technical progress pose a threat for privacy of your past actions?
- CoinJoin transaction says that N coins were simulaneously spent, all the values are transparent, so there's nothing to break in this sense.
- Zero-knowledge proofs have different variants. Quantum resistance and even more strength is possible, but this is a nuance of concrete cryptocurrency.
(The other two protocols are outside of my knowledge and interest)

[wajik-tempe]

Monero's combination of RingCT and Confidential Transactions is widely regarded as one of the most powerful privacy solutions among the options listed. RingCT conceals transaction amounts and sources, whereas Confidential Transactions conceal transaction quantities. The usage of ZKPs by Zcash provides robust privacy, although it has been chastised for optional visible transactions and lengthy trusted setup processes. Grin's Mimblewimble provides strong anonymity but lacks certain of Monero and Zcash's sophisticated capabilities, such as private quantities. Monero's emphasis on privacy by default and comprehensive privacy features make it an excellent alternative for people wanting the highest level of financial privacy and anonymity.

[VFalcon]

Now Fairspin has a good approach, they have been doing all sorts of cool tournaments and giveaways lately, and in the last tournament I participated and managed to get $50, you might get more if you are more active than me. And they have a new Fruit bounty bonanza tournament going on.

[Abiky]

Monero's combination of RingCT and Confidential Transactions is widely regarded as one of the most powerful privacy solutions among the options listed. RingCT conceals transaction amounts and sources, whereas Confidential Transactions conceal transaction quantities. The usage of ZKPs by Zcash provides robust privacy, although it has been chastised for optional visible transactions and lengthy trusted setup processes. Grin's Mimblewimble provides strong anonymity but lacks certain of Monero and Zcash's sophisticated capabilities, such as private quantities. Monero's emphasis on privacy by default and comprehensive privacy features make it an excellent alternative for people wanting the highest level of financial privacy and anonymity.

Zcash eliminated the need for a trusted setup with the introduction of the NU5 network upgrade. The developer team decided to take this route instead of switching to ZK-STARKS. ZEC is now more decentralized than ever with the upgrade and the removal of the "founder's fee" (which was a sort of tax collected from miners to fund the project). The cryptocurrency is aiming to become a full-fledged PoS blockchain network in the future. This will set it apart from Monero, Grin, and the likes. But I hardly doubt adoption will increase, especially when governments are against privacy coins. They've spread false propaganda/misinformation to prevent as much people as possible from getting into such cryptocurrencies.

I believe both Monero and Zcash have strong privacy methods, but none can replace the other. After all, each method has its own advantages/disadvantages. Which one to use would depend entirely on your privacy needs. As long as the aforementioned coins stay decentralized, nothing should be able to stand in their way. Just my two sats.