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by alvarosm 3494 days ago
You need a ton of space and/or processing power for the zero-knowledge transactions. The anonymity isn't free!

In practice Zcash/zcoin (different tradeoffs) are of no use to you unless you are willing to go the extra mile to hide something (criminal activities and such). There's no point in paying for the extra effort for normal transactions.
2 comments
nickik 3494 days ago
Anonymity of the system as a hole is the value. Just like with Telegram and the concept of a secret chat, you should not only use anonymity if you particularly need it. Anonymity and Security should be the default and you should optionally to be able to not have it.

Maybe even if I don't need the anonymity now, maybe in 10 years I will, and then I don't want to start using them because that change provides information.

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detaro 3494 days ago
How large is the overhead in numbers? I tried to search but didn't find any clear examples.

EDIT: found some data in the ceremony report linked elsewhere in this discussion: https://petertodd.org/2016/cypherpunk-desert-bus-zcash-trust...

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petertodd 3494 days ago
Sending takes a few minutes of computation on your wallet - but that's not such a big deal as it's comparable to the time it takes for block confirmations anyway.

The problem is verification of private transactions is very slow by cryptocoin standards, and verification is something that every full node and miner must do. Zcash would fail if private transactions were used in large numbers, as blocks would take too long to validate for mining to remain decentralized; Bitcoin transactions are a few orders of magnitude faster to validate, with a 4x more conservative block interval and 2x smaller blocksize, and the Bitcoin dev community has had to make heroic efforts to further optimize validation.

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daira 3493 days ago
There are ways to significantly reduce the cost of zk proof verification by batching (that are compatible with the existing Zcash protocol without a fork).
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petertodd 3493 days ago
Prove it first by actually implementing those ways and having them survive peer review; this is highly experimental crypto so it's not clear what's actually possible.

Again, I don't think it's very responsible to knowingly release design a protocol that in its current form would collapse if heavily used due to a lack of safety limits.

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