The Zcash Anonymous Cryptocurrency [video]
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Also, Zcash had an initial trusted setup ceremony after which the 6 participants supposedly all deleted their private keys. You DO have to trust none of those have colluded to someday, for example, start creating zcash coins for their own good without anyone knowing. All the info here: https://petertodd.org/2016/cypherpunk-desert-bus-zcash-trust...
You don't need an exchange to use z-addresses, just receive into a one-use t, and then make it disappear into your main z-address yourself.
Finally, you have to trust that AT LEAST ONE won't collude, because you need all pieces to fake Zcash, which is very different.
Enough with this FUD. It's innovative tech, I expected HN to appreciate it more than the usual cryptocurrency circles.
Theres a good academic read about this here: https://lab.getmonero.org/pubs/MRL-0001.pdf and here: https://lab.getmonero.org/pubs/MRL-0004.pdf
And also a privacy improvement which gets into effect in about 25 hours or so with the next hardfork called RingCT, which has been peer reviewed by Ledger journal: http://www.ledgerjournal.org/ojs/index.php/ledger/article/do...
Optional privacy a la ZCASH is broken by design and cannot work, you are still able to have tainted coins and do blacklisting etc, its effectily useless, also it opens up a whole world of other attack vectors like this one: https://github.com/zcash/zcash/issues/1360#issuecomment-2461...
A good read for everyone unbiased tho a bit old is here (which explains the inner workings): https://lab.getmonero.org/pubs/MRL-0003.pdf
- multisig with zaddresses seems not to be possible. - Using Z Addresses on a Smartphone or HW device like Trezor is too resource intensive
Looks like a privacy disaster to me, as no one will be using it.
As to the trusted setup, there are a few salient points:
- you don't have to "just trust one participant", what if 3 of them collude and 3 were compromised?
- every participant booted off the same ISO which was provided by a single person. The claim is that the ISO can be built deterministically, but that still does not prevent it being compromised in subtle ways, and it seems that hardly anyone has bothered to try verify the ISO build process even subsequent to the ceremony.
- even when there was clear evidence that someone's phone was compromised, the ceremony went ahead. This is a huge red flag - why not just stop the ceremony and rethink it, given the fact that there was obvious infiltration?
- why only 6 participants? Why were they chosen by Zooko? Why was there no open application process where applicants could be considered by the community? Why were no members of academic institutions involved as participants?
The way the trusted setup was conducted is shocking, this is privacy theatre at best.
On your closing remark about it being innovative: nobody doubts that the ZeroCash white paper is innovative, but it is also too new for us to be trusting it. Would you advocate for TLS 1.3 to default to only use some encryption method that was in a very recent, largely unreviewed whitepaper, especially when that whitepaper contains math that is particularly hard to grok (Greg Maxwell calls it "moon math")? Why do we hold all of our cryptography to such high standards, distrusting everything that is new and unproven, but we're expected to give a financial system a pass? Would you feel the same if all of your net worth was held in that financial system?
Both Zcash and Monero (plus perhaps Dash, but it has some issues) try to augment Bitcoin with some privacy guarantees.
Ethereum is extending Bitcoin with Turing-completeness.
I follow Bitcoin, Ethereum and Monero with interest. I wonder whether any of these additional features will prove advantageous enough to surpass Bitcoin, which is more mature and has much bigger market cap right now.
IMHO, Bitcoin is secure enough for its current main use-case, which seems to be escaping Yuan / Bolivar. But I might be proven wrong. It's also interesting to note some other black swans may trigger cryptocurrency adoption in 2017 [1].
Ethereum seems advantageous for many business applications which are impossible with a traditional blockchain, but they really need to ensure Turing completeness doesn't lead to more fiascos. Perhaps by enforcing much much better static analysis than currently available [2]. You can err on the safe side and reject contracts that don't pass whatever static analysis. Seems the only way to retain Turing-completeness and safety.
However, given EVM semantics is complicated, perhaps a redesign will be needed so that static analysis does not rule most contracts as potentially unsafe.
[1] https://s3.amazonaws.com/storage.saxobank.com/TradingFloor/2...
You must be joking.
I don't follow bitcoin very closely. Could you please tell me more about escaping yuan/bolivar? It seems to me that if you have access to bitcoin, it means you have banking capabilities and access to the internet. Once you have these two, you can use paypal or similar and store EUR or USD. Volatility of USD is way lower than bitcoin?
How would you do this?
If it is possible to exchange yuan to usd and keep it in paypal without a US account, I would still be very uncomfortable storing hundreds of thousands of dollars in it. It is a centralized entity that can freeze funds for any reason, be compelled to report things, make mistakes, paper trail, etc.
Being able to exchange currencies is also a step above regular banking I believe. You need access to forex markets and the associated setup and trails.
Likely means using Bitcoin to evade currency controls, which they have in China and some South American countries e.g. Argentina[1].
[1] http://www.coindesk.com/bitcoin-thriving-argentinas-black-ma...
In China it seems the preference is to buy bitcoin mining equipment in yuan and generate bitcoin to sell, taking advantage of the cheap electricity available in China and writing off some of the capital investment via tax. Although there is significant trade on Chinese exchanges much of this is often thought to be suspect due to the lack of trading fees which means fake/self trades are available at no cost.
But Zooko's name is well-known around the traps whereas Monero -- not.
Zcash offers more anonymity at the expense of more computational resources.
All the developers of Zcash were in the audience and then there is some associated guy giving a intro.
I thought it was a bit pointless.
ZCash, at least for the first 3 builds, did not have their primary feature (fully anonymous transactions) working. I don't believe thats fixed yet (is it?). How they missed their primary feature being broken before releasing, I have no idea.
Any other source for this claim?
Per the ZCash website (https://z.cash/blog/state-of-the-network-2016-10-31.html) -
"There is one known bug, which causes private transactions (those in which all of the inputs and outputs are shielded addresses) to not get mined."
Please stop spreading FUD about zcash.
- https://github.com/zcash/zcash/issues/1705
- https://www.cryptocoinsnews.com/zcash-bug-prevents-private-t...
https://github.com/zcash/zcash/commit/9eb852edd0c9a20d7e3925...
As to the video, the talk was pathetic. The speaker claimed he was going to explain zk-SNARKS to the layperson, then immediately claimed to not understand them. It presented none of the risks of ZCash, and only really covered how joinsplits work.
Also the corrupt terms of the zcash social contract make it abhorrent to many of us, who believe in open source, peer-review, and decentralization of authority, as well as casting deep suspicion on the motivations of the beneficiaries of zcash's corporate structure, and the acts which self-interest will therefore dictate.
May be we should all abandon the privacy ship, join the Monero guys (no matter its obscure origins by the way) and spread FUD and lies about any better tech like Zcash or others that comes up, right?
Also, obscure origins are irrelevant when the technology is solid. Take the following examples: TrueCrypt, Bitcoin, MimbleWimble. Are you honestly arguing that TrueCrypt was bad?
If you don't like that, there is already the Zclassic fork wihout the founders fee.
Both Bitcoin and Monero have fair distribution; development of neither is done by for-profit LLCs financially supported by any pre-mine, miner tax, insider investment/ICO, or other fancy scheme paid out by either the underlying monetary system or taxed from the users and/or those securing the network, and while Blockstream Inc. does employ Bitcoin Core developers, Monero development is entirely decentralized without even a foundation to its name.
"At first, 50 ZEC will be created every ten minutes. 80% of the newly created ZEC will go to the miners, and 20% ZEC to the founders.
Every four years, the rate of ZEC being created will halve (again, just like in Bitcoin). After the first four years the ZEC created per ten minutes will drop to 25ⓩ, but after the first four years, 100% of it goes to the miners."
https://z.cash/blog/funding.html
"At first, 50 ZEC will be created every ten minutes. 80% of the newly created ZEC will go to the miners, and 20% ZEC to the founders.
Every four years, the rate of ZEC being created will halve (again, just like in Bitcoin). After the first four years the ZEC created per ten minutes will drop to 25ⓩ, but after the first four years, 100% of it goes to the miners."
"The 10% of the total supply that makes up the Founders' Reward is distributed between launch and the first halving (at block 850,000). During this period (which will last approximately four years), half of the total monetary base will be generated. After the first halving, there will be no more Founders' Reward, and all newly-created ⓩ will be received by miners."
https://z.cash/blog/founders-reward-transfers.html
I make no judgment on whether this is good, or bad, or other, just wanted to present the source's position on the matter.
1. It's controlled by a corporation with VC backing. This leads to a single point of failure, a ton of disincentives, and makes it easier for an attacker.
2. The cryptography is untested, unproven, and too new to be trusted. Since when did technically competent people advocate for cryptography like that??
3. The 20% tax puts a crazy amount of strain on the economic system, and is inordinately high.
4. The trusted setup is hard to get right, but they completely screwed it up (see my comment upthread).
5. Private transactions take 8gb+ of RAM and several minutes to compute on my laptop, how is that at all scalable or useful?
We should be immensely critical of new cryptography being rushed into production at the behest of investors, and we should not be promoting a centralized, corporate-controlled cryptocurrency.
1. As a Bitcoin fork and descendant it is not controlled by anyone but by its network of users. Therefore there is no single point of failure. Development is done today by a corporation with VC backing which does not necessarily mean that will continue to be the case tomorrow. A community of developers and/or users can take the development leadership at any point in the future if it were so needed.
2. The cryptography is currently superior to any other. It has been tested and proven. It is in your hands to prove it wrong. Please do so.
3. The founders reward provides even more security and development resources during the first 4 years. Many people see it in fact as an advantage.
4. The trusted setup process whitepaper has been made public, plus the participants are also known. You can research and certify the process and contact the participants as you wish since it is all public. Please provide the exact point of failure in the process and where exactly has it failed. It seems like a highly secure setup to me.
5. The RAM and time required for private transactions can be done with no problem at all by most users with laptops as of today. Even so, there is development going on by the Zcash team to improve the performance and reduce the ram and time required.
In the spirit of Bitcoin, Zcash is decentralized and built for privacy loving users.
2. No, it's not in my hands to do so. The onus is on ZCash to demonstrate this the way any other cryptography is proven: peer review, and time. ZeroCash has little of either.
3. Anyone that sees it as an advantage has no clue about disincentives or game theoretic attacks.
4. The exact point of failure is that they all booted off the same ISO that was provided by one person. Additionally, when an observer at one of the stations had their phone compromised they didn't shut the ceremony down and restart, they just continued. Also, the participants are just Zooko's buddies - who's to say they aren't conspiring together, and merely compromising the procedure for anyone who isn't part of that (e.g. Peter Todd)?
5. If privacy is not the default, and is immensely hard to use (due to the system requirements), it will hardly be used. The entropy of the private system will be restricted to a relative handful of users.
1. You will probably be surprised that there are a lot of highly qualified people in the community already.
2. If it is so unproven and so untrusted, please go ahead and break it. Words are cheap, mathematical proof and action is what counts.
3. Remains to be seen who is right on this one and we will see it during the next 4 years when the founders reward expires.
4. Conspiracy theories. Well, there will probably be more setups in the future. May be you want to propose a counter-whitepaper with a better way to do the cryptography setup and even be part of the ceremony itself?
5. Zcash uses mathematically proven privacy. Privacy loving users will use it. Research the tech and then may be you will be inclined and destined to use it too.