dash is an old hand at the Kryptowährungen and uses an innovative model of governance. There are so-called master Odes which allow to include private send transactions in dash. We look at how private it is really in dash and what may possibly compromise the privacy, us in this article.
The fundamental feature of dash is the network of master Odes features
as mentioned, the level-2 scaling opportunities create. The two most important functions for the dash network are here the features “ InstantSend ” and “ PrivateSend “. To make a master ODE, 1,000 dash as collateral must be frozen. This corresponds to currently just under $ 800,000. In return for their services, the master Odes received 45% of the block rewards (approx. 7 dash per month / master ODE).
dash offers a native CoinJoin service network, with the name PrivateSend . CoinJoin means that their coins in a pot raise a group of users, and mix. For a third party, so the unique origin of the individual coins is obscured.
One can imagine that the principle of mixing: it flies in a helicopter over a highway and has a red car. The mixing is in this example of how a bridge under which to lose the car out of sight for a moment. On the other side of the bridge, now on two (or more) red cars to the fore, so that you no longer can be sure which car is the original.
The process of coin mixing runs at dash in the background and following these steps :
- the PrivateSend transaction is in default values (0,01 dash, dash 0.1, 1 dash, 10 dash…) download broken.
- The wallet sends a coin-mixing request to the master Ode network.
- A mixing session begins when two users send a similar message, in which the default values are the same. A randomly selected master Ode mixes all inputs and then instructs the respective wallets themselves to pay back the money himself, but on a so-called change of address.
- To have more security, starts a new mixing session. With each round, exponentially increases the number of possible coin-mixing devices and makes it therefore more difficult to track the origin of coins.
- This process runs in the background of the wallet, so the stocks are already anonymized, if a user would like to make an anonymous transaction.
A maximum of three persons participate in a mixing round. The maximum number of rounds of mixing is eight. The number of potential participants is listed in the following table:
|number of rounds||possible participants|
 19659003] two of the most problematic attacks are illuminated more accurately in the following section:
master Ode snooping attack
to anonymize dash, determines a random master ODE with the process of CoinJoin. For this master ODE, the process is completely transparent, that is, the input – and output addresses of participants are shown. If a “malicious” master Ode records the PrivateSend transactions, so the privacy is compromised. This attack is mitigiert to the part of this that you can – mix up to eight rounds so theoretically eight different master Odes is associated. The more malicious master odes in the network are the achieved privacy is less. The number of master Odes is limited by the required 1,000 dash. The current money supply by 7.836.000 dash are maximum 7836 master Odes. Currently, there are approximately 4,500 . A projection of costs for about half of all master Odes is $1.687.500.000. Seriously attacking the network is so at least not cheap.
is not a master Ode “evil”, but a peer who takes part in the CoinJoin In contrast to the master Ode snooping attack a Sybil attack. A malicious participants of a CoinJoin has privileged information about the source and the target of a transaction and can exclude his own coins. The cost of a Sybil attack is only the transaction fees for a PrivateSend transaction.
Current state of the art of
are known while solutions for the two mentioned problems, the vulnerabilities have been eliminated. The master Ode snooping attack can be mitigiert by a so-called ‘master Ode blinding’. This means that the master Odes even know anything about the origin or the destination of a PrivateSend transaction.
The Sybil attack could be circumvented by a round of mixing with itself. It is necessary, however, that are not of actual multi parties mixing to distinguish the transaction. Again, this isn’t in the dash is currently integrated Protocol.
For your own privacy, it is advisable to use the maximum possible number of rounds of mixing. However this can be more expensive compared to other transactions in the dash network.
Look into the future
with dash evolution should be redesigned the PrivateSend feature. Master Ode blinding should be implemented. The release of the DashPay evolution wallet on the Livenet is to be published in the February 2018 .
dash is a Kryptowährung with a unique governance model of master Odes. The master Odes enable the feature “PrivateSend”, in which participants mix their dash into a CoinJoin and thus disguise the origin. The reached anonymity is not based on Cryptography (such as RingCT locally or zero knowledge proofs in Zcash ) and can currently be compromised by malicious users in the system. For maximum security, I recommend always to use the maximum number of rounds of mixing.