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ZCash Will Be a Truly Anonymous Blockchain-Based Currency

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Re: ZCash Will Be a Truly Anonymous Blockchain-Based Currency

#281

Earlier quoted context omitted.

>There just aren't enough bits in the transaction to identify you. From the ZCash Whitepaper: >A powerful attacker could potentially fabricate an additional block solely for a targeted user. Spending any coins with respect to the updated Merkle tree in this “poison-pill” block will uniquely identify the targeted user.

That would only tell you that a given network participant is making a transaction. The inputs, outputs and amounts are all still private.

So what? That is the opposite of anonymous. That's the point.

Re: ZCash Will Be a Truly Anonymous Blockchain-Based Currency

#282

Earlier quoted context omitted.

>I don't know much about ZCash ZCash has this ability to de-anonymize users through targeted blocks, and is a privately-held U.S.-based company that claims no liability for it's user's actions, meaning if subpoenaed they will [probably] turn over information. They're also privately cashing in on 20% of all transaction fees. Just because someone behind a project has credentials you respect doesn't mean we should ignor…

> Just because someone behind a project has credentials you respect doesn't mean we should ignore aspects of the project. I agree. Good thing that's not what I did. Regardless of any flaws, there has clearly been a lot of effort put into it by multiple smart people with good intentions (from what I can tell), therefore it is unfair to characterize it as just "another altcoin". That's the only assertion I made.

But when you look at the characteristics of ZCash, it is just another garden variety alt-coin, despite the credentials of the people behind it.

Re: ZCash Will Be a Truly Anonymous Blockchain-Based Currency

#283
post #39

Another altcoin. This one has a 10% pre-mining cut for the founders: "Zcash's monetary base will be the same as Bitcoin's — 21 million Zcash currency units (ZEC, or ⓩ) will be mined over time. 10% of that reward will be distributed to the stakeholders in the Zcash Company — founders, investors, employees, and advisors. We call this the “Founders Reward”." Here's a list of the other 709 altcoins.[1] 373 of them are st…

I went to a talk at Stanford by Eran Tromer on Wednesday, in which he described some of the theory behind Zcash. He made a lot of very strong claims about his new approach to computer security. There was a lot of hand-waving. I don't understand exactly what he's claiming, and what he claims to have proved. You can watch the video yourself and try to figure it out.[1]

Tromer's paper [2] may be helpful. At least there, the references are cited and findable. Tromer's first result deals with collision-resistant hash functions. That's been a big headache in practice. It's really hard to develop a cryptographic hash function for which someone can't create two strings that result in the same hash.[3] MD4 and MD5 have been broken, SHA-1 has been partially broken, and SHA-256 hasn't been (publicly) broken yet. Tromer seems to claiming that he has a solution to weak hash functions. But it's really hard to tell from his writing.

Anybody really understand this?

[1] http://web.stanford.edu/class/ee380/ [2] http://www.cs.tau.ac.il/~tromer/papers/huntingsnark-20140724... [3] https://www.cs.cornell.edu/courses/cs6830/2009fa/scribes/lec...

Re: ZCash Will Be a Truly Anonymous Blockchain-Based Currency

#284

Earlier quoted context omitted.

That would only tell you that a given network participant is making a transaction. The inputs, outputs and amounts are all still private.

So what? That is the opposite of anonymous. That's the point.

You do not know anything about the transaction. Not the amount, not the sender. Just that it happened.
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