Bitcoin Forum

Anonymous transactions on a blockchain are a big deal and has been subject of research in the last few years, now DASH claims that its built-in mixing ability (darksend) is anonymous, I'm wondering how anonymous is it, say compared to a coin mixing service, which from my research is not actually that anonymous. Thanks for any info.

Its fully anonymous in a decentralised way, integrated on protocol level and is optional.
It uses a thoroughly improved and adjusted CoinJoin to accomplish that.

Compared to a coin mixing service it is a lot more decentralised and does not have the risks associated
with centralised mixing services.

In its total existance Darksend (renamed to PrivateSend recentely) has never been broken and the vulnerabilities that were found by an external audit
from Kristov Atlas in 2014 (when it was still closed source) were quickly patched up and Darksend has been opensourced soon after that.

link :

http://cdn.anonymousbitcoinbook.com/darkcoin/darksend-paper/Atlas_Darksend-Analysis-v001.pdf
http://blog.anonymousbitcoinbook.com/2014/09/darkcoin-code-review-results/
https://www.dash.org/forum/threads/reply-to-kristovs-paper.2325/

Update 12.1 (in development) is focussing on making the whole Darksend / Privatesend proces more efficient and faster, its currently undergoing
testing on Testnet.
 
link : https://www.dash.org/forum/threads/v12-1-testnet-launch-thread.9014/

Well that is quite impressive. Is there any other method of doing anonymous transactions currently? (Whether its a service on top of bitcoin or another cryptocoin which implements an anonymous feature)

Also, why is it a seperate action in the protocol and not a standard (all transactions anonymous).

There are a number of other altcoins that have a strong focus on anonymity but the anonymity there is either not optional (its anonymous by nature) or they have
totally different (and therefore uncompatible with Bitcoin) blockchains like for example Cryptonote altcoins. Dash on the other hand is forked from Bitcoin and
is therefore much more easy to implement by merchants who are already using Bitcoin for their payments.  


As i understand it is to maintain tracebility through blockchain explorers, used in such a way it obscures the links beween sender and receiver,
making it impossible to trace transactions back to sender (when using Darksend / PrivateSend) and users that dont want to have anonymity in their transactions
can also still use it. Basicly its about giving options to users.

Yes Monero, https://getmonero.org/home (https://getmonero.org/home), uses ring signatures to mix with existing prior transactions on the blockchain. There is no need for a separate action for mixing  (Coinjoin, or a mixing server), or to wait for a period of time until mixing is completed before sending mixed funds since mixing is built right into the Monero protocol. When one sends Monero mixing is built right into the send funds transaction.

Edit: In Monero anonymity is not optional, since there is a minimum mixing level required for each transaction, currently 2 and scheduled to increase to 4. The only exceptions are certain dust clearing transactions and coinbase (generation of new coins) transactions.

I don't think it's completely correct to say that anonymity is not optional for Monero, since you could publish your view key and allow anyone to audit your txs, right?

Vcash has an autonomous crypto-currency mixing and anonymizing mechanism called Chainblender. Chainblender allows Vcash users to send and receive anonymous transactions with optional use of the ZeroTime feature (instant transaction). Vcash allows for instant and anonymous transactions without blockchain bloat.  

Yes that is a valid point; however when it comes to transactions on the Monero blockchain there is by design no option to not mix. This makes Monero fundamentally different from Dash and also fundamentally different from some other Cryptonote coins. This is important because by enforcing anonymity at the protocol level certain attacks can be eliminated or at least mitigated. There was extensive discussion of this in https://lab.getmonero.org/pubs/MRL-0004.pdf (https://lab.getmonero.org/pubs/MRL-0004.pdf).

Publishing a view key is in many ways analogous to publishing a financial statement. The data is inherently anonymous but one explicitly chooses to make it public or share it with a certain group (those to whom the view key or the financial statement is provided).

V.cash thread https://bitcointalk.org/index.php?topic=1504342.0

"How anonymous is DASH's "darksend mixing" actually?"

Listen to the developer of dash himself (~min 1:50)

https://www.youtube.com/watch?v=x5sNx7SMTP8

Until dash implements an end-to-end method for privacy, this will be the case.

So anonymous... Like Bitcoin ::)

problem is that exposes all your transactions and your whole wallet history. with monero it's either you see everything or you see nothing, that's a big problem.

here is my reply to a monero troll post in the DASH thread....

Except to do so (configure their own visible/invisible blockchain settings) with monero would require running multiple wallets with separate view keys last i checked. Even a small charity would have to run several monero wallets. A larger charity for say battered women would need to run a separate wallets for every person they help/sent money to. Just to comply with banking and healthcare related laws for said charity would take several wallets with separate view keys. An official GUI wallet would probably help manage all those wallets but not much!  ;D

Or you could just use a single DASH wallet, problem solved.

That's not true Shadowcash is bitcoin based and works on a duel token system that allows you to choose between traceable or non-traceable transactions http://aboutshadow.com/index.php/shadowmarket/q-a

"ShadowSend’s anonymous cryptographic transaction protocol uses dual-key stealth addresses, traceable ring signatures (presentation of the anonymous cryptographic transaction protocol which utilizes the above mentioned cryptographic principles). We explain how Shadow introduces a much higher level of privacy and anonymity to the network while still preserving the core principles of trustless decentralization, unforgeability and double­spend prevention. We also presented performance data of our scheme including proof sizes, signature generation times and verification times in our ShadowSend Whitepaper"

https://i.imgur.com/2XTQhYF.jpg

https://doc.shadowproject.io/#shadowsend-v2-0

that shadowsend v2 slide looks real good. is that all implemented or is it just vaporware right now? eta?

from what you wrote it looks like shadow has come a long way since i last checked. i'll do some more research and i may just pick up a few.
for people who just want to safely and quickly mix small amounts of btc i always recommend using shapeshift/coinomi and shadow rather than monero. i trust shapeshift way more than slower 3rd party monero services/options.

what size is shadow blockchain?

looks like monero propaganda from a infamous monero troll to me.  :P

What specifically do you find at fault in that presentation? Please, keep it technical.