DASH - Reading Assignment

[DavidZed]

1. What information does PrivateSend conceal, and by what method?
   Conceal the addresses by mixing your input with other inputs, in a single transaction, using coinjoin method

2. How do masternodes improve on the initial CoinJoin proposal?
   Masternodes mix and matches

3. Alice send some DASH to Bob using PrivateSend. Describe how an attacker could link their addresses.
   If the masternode is a psy, or somebody can spy on the masternode to get the information of their information.

4. In what way could PrivateSend be more risky than a normal Bitcoin Transaction?
   The user is seen as private, which is could be seen as suspicious

[JJ.kush]

1. The private seed conceals the amount the user is sending. By breaking it down into standard denomination of 0.001, 0.01, 0.1, 1 and 10 dash. The Dash is then mixed up with other Dash in a transaction.

2. The masternode does all the work. Not requiring someone to construct the CoinJoin transaction.

3. If an malicious character is running a master node they have access to senders and receivers address.

4. All the trust is in a relatively centralized network of masternodes.

[Vitalii]

1. It conceals the origins of your funds by mirroring different inputs (making them being seen as discrete coins)
   2 Masternodes do all the matching work themselves which in turn is more convenient than in CoinJoin.
2. By being the host of that particular masternode on which mixing took place or by compromising that very masternode.
3. The hosts of the masternodes potentially could be bad actors

[muradawad]

1. Ownership of the coins through Coinjoin.

2. By mixing the coins ia a standard denominations.

3. Through connecting to the masternode.

4. Masternodes could be controlled by different sides.

[ghiasi12reza]

1. What information does PrivateSend conceal, and by what method?
   PrivateSend uses an innovative process to mix your inputs with the inputs of at least two other people in a single transaction, so the value in Dash never leaves your wallet. You retain control of your money at all times.

2. How do masternodes improve on the initial CoinJoin proposal?
   the process happens through master nodes.

3. Alice send some DASH to Bob using PrivateSend. Describe how an attacker could link their addresses.
   All master nodes are running through a private server and if an attacker gets access to these servers then will be able to gain access to those infos.

4. In what way could PrivateSend be more risky than a normal Bitcoin Transaction?
   If you use private send you are already suspicious. You gotta hope that masternodes is not influenced/corrupted.

[StaknSats]

1. What information does PrivateSend conceal, and by what method?

Conceals the sender origin and receiver destination by Mixing commonly denominated transaction inputs into one transaction (coinjoin) and by the masternodes also doing the mixing over and maybe over and over again up to 16X, as directed by the user, called mixing rounds, provided backup is enabled so backup wallet addresses can be created, as may be req’d

2. How do masternodes improve on the initial CoinJoin proposal?

Thanks to this innovative two tier network , PrivateSend gives financial privacy through a decentralized implementation of CoinJoin, so by masternodes performing the CoinJoin function, Dash can combine and offer innovation features in a trustless and decentralized way.

3. Alice sends some DASH to Bob using PrivateSend. Describe how an attacker could link their addresses.

The attacker could be the masternode or the masternode’s security could be compromised so, as the compromised masternode knows the originator and destination of the transaction(s), so will the attacker know the transaction details

4. In what way could PrivateSend be more risky than a normal Bitcoin Transaction?

Bitcoin is trustless and this is not

[barney]

DASH - Reading Assignment

1. What information does PrivateSend conceal, and by what method?
   PrivateSend gives you true financial privacy by obscuring the origins of your funds.

2. How do masternodes improve on the initial CoinJoin proposal?
   Any of these Users would not need to construct this transaction.
   The masternode would find other people automatically, who wish to mix the same denomination.
   The masternode will then mix up the inputs and instructs from all users’ wallets.

3. Alice send some DASH to Bob using PrivateSend. Describe how an attacker could link their addresses.
   If the Attacker would have control over the masternode, he/she could link Alice’s and Bob’s addresses together.

4. In what way could PrivateSend be more risky than a normal Bitcoin Transaction?
   The users who want to use PrivateSend might send a suspicious message to the ones who control the masternodes.
   The users do not know who is behind the masternode, if that would be someone who might want to f.ex. expose them to government for using such privacy (trying to remove the traceability).

[Boondre]

1. What information does PrivateSend conceal, and by what method?
   The link among the inputs and outputs of a transaction, it is an implementation of Coinjoin.

2. How do masternodes improve on the initial CoinJoin proposal?
   Not requiring someone to construct the Coinjoin transaction, masternodes collect and mix the coins.

3. Alice send some DASH to Bob using PrivateSend. Describe how an attacker could link their addresses.
   Hacking the MasterNode or by running it, in both cases it would be easy to retrieve the information about them.

4. In what way could PrivateSend be more risky than a normal Bitcoin Transaction?
   If the master node is corrupt and people can see that you have used PrivatSend which shows that you might have something to hide.

[Cajasky]

1. What information does PrivateSend conceal, and by what method?
2. How do masternodes improve on the initial CoinJoin proposal?
3. Alice send some DASH to Bob using PrivateSend. Describe how an attacker could link their addresses.
4. In what way could PrivateSend be more risky than a normal Bitcoin Transaction?

1- It mixes your inputs with the inputs of at least two other people in a single transaction.

2- Masternodes collects and mix the coins.

3- By running a dishonest masternode.

4- Masternodes are the kind of trusted third party that you wanted to avoid in the first place.

[bdoherty]

1. What information does PrivateSend conceal, and by what method?
   Hides your inputs by mixing them with other users.
2. How do masternodes improve on the initial CoinJoin proposal?
   Your inputs are mixed with other random users who you know nothing about nor they know about you.
3. Alice send some DASH to Bob using PrivateSend. Describe how an attacker could link their addresses.
   I have no idea! I don’t see how they could link them. The masternodes don’t have any identifiable information about the users…
4. In what way could PrivateSend be more risky than a normal Bitcoin Transaction?
   Not sure, maybe if the masternodes collude with each other but even then i don’t see how

[Alko89]

@bdoherty

The masternodes don’t have any identifiable information about the users…

The masternodes are aware of the addresses used so a malicious node could link them.

[madingo]

Dash - Readig

1. PrivateSend conceal the origins of a fund. They use an innovative process to mix the inputs of at least two other people in a single transaction.

2. Masternode improve on the initial Conjoin proposal by automatically mixing the coins and will not need the senders to sign the transaction inputs and outputs.

3. "Alice send dash to Bob " A masternode could be run by an attacker on a private server, increase inputs could lead to the possibility for the attacker to map out the transactions linked to Alice and Bob.

4. The way a PrivateSend could be more risky than normal Bitcoin transaction is the fact that, the masternodes that are responsible for the transaction are chosen and are limited, they are easy to target by an attacker. While the normal bitcoin is open to many network nodes to propagate the information of a transactions,this makes it difficult for an attacker.

[Cestrada]

1. Privatesend conceals identity of sender and receiver by using a decentralized coinjoin method.
2. Master nodes improve on the initial coinjoin proposal because with chainlock to prevent reorganization. Is this correct?
3. If the master node is attacked? Or if not enough rounds? Or if odd amount in change address? Not sure. Help.
4. Private send is known by the master nodes by its nature to be a private transaction rather than a typical transaction like on the Bitcoin network which then may be suspicious to anyone interested. Is this correct?

[Alko89]

@Cestrada

Master nodes improve on the initial coinjoin proposal because with chainlock to prevent reorganization. Is this correct?

Masternodes basically provide an automated coinjoin method. So the parties don’t have to coordinate the tx by themselves.

@Cestrada

• If the master node is attacked? Or if not enough rounds? Or if odd amount in change address? Not sure. Help.

If the masternode is run by a malicious party the privacy could be compromised.

@Cestrada

Private send is known by the master nodes by its nature to be a private transaction rather than a typical transaction like on the Bitcoin network which then may be suspicious to anyone interested. Is this correct?

This is not the case in a normal coinjoin tx because they don’t rely on a system of masternodes to coordinate it.

[Mihir23]

1. PreventSend improves privacy by concealing the address of the sender and the target receiver by implementing a method - CoinJoin.

2. When a Dash wallet sends a mixing request to a masternode, it contains information about the number of denominations of Dash that would like to be mixed. The masternode will then create a session ID which gets broadcasted to all the nodes in the network. This ID is sent to a mixing queue, where the user’s wallet consults the network to find matching denominations of Dash from other mixing requests. If at least three mixing requests have a match, the masternode arranges a mixing session. The masternode then verifies that all the inputs and outputs from each wallet are valid and mixes together into a combined transaction. This entire process is coordinated and automated by the masternode without needing someone to combine the multiple transactions into a single transaction.

3. The attacker can either run or compromise a masternode and link which inputs belong to the original senders’ address in the mixing session. The attacker can also find the designated addresses of the receivers from the outputs.

4. The government can run its masternode and track which addresses are frequently using PrivateSend. It can make users the potential suspects of illegal activities such as money laundering. Criminals can also run a masternode to monitor the activity of an address in an attempt to find the common owner.

[cge5009]

1. It conceals the history of the coins that you own by combining them with others holders coins and then resending a new Transaction to a different address that you own.

2. Masternodes make it possible to do the mixing without the coins having to leave your possession. This means less trust on your part and less a chance that an outsider actor will intercept or take them.

3. If the attacker can get information from the master node than they could determine who and how much money was sent.

4. Everyone will know that you used privatesend by seeing the block history which could lead to problems.

[Sam_Clare]

1. What information does PrivateSend conceal, and by what method?

It covers up the outgoing address and the amount by combining a number of transactions together and mixing them up.

2. How do masternodes improve on the initial CoinJoin proposal?

Masternodes wait for a number of people requesting the same denomination then launches a round that mixes the coins up. Users can opt in to further rounds of coin mixing to make it even more difficult to trace.

3. Alice send some DASH to Bob using PrivateSend. Describe how an attacker could link their addresses.

If all of the masternodes were somehow hijacked then an attacker could find out which RX and TX matchup as its the only place that information is held.

4. In what way could PrivateSend be more risky than a normal Bitcoin Transaction?
   You need to have trust in the people running the nodes and hope they never publish log files.

[bbss]

1. PrivateSend is an implementation of CoinJoin. The original sender and receiver of money are hidden.
2. Masternodes collect coins from different users, divides them by 10, and sends to original receives amounts broken into smaller amounts divided by 10.
3. The attacker can run the masternode.
4. Masternodes could be run by malicious entities. The entities can spy the network and determine patterns that link senders and receivers.

[Alko89]

@bbss

divides them by 10, and sends to original receives amounts broken into smaller amounts divided by 10.

I has some defined denominations, not necessarily by 10

[Uyan]

1. PrivateSend, an implementation of CoinJoin, conceals the link between sender and receiver, thus also concealing the ownership history of the network’s coins. It does this through the method decsribed by CoinJoin, which mixes transactions of multiple users by joining transaction inputs in a single transaction.

2. Masternodes improve on the initial CoinJoin proposal by acting as a matchmaking system that is given no identifiable information, so you no longer have to find users to team up with by yourself or trust the users who you join transaction inputs with.

3. Alice sends DASH to Bob using PrivateSend. If an attacker could control a masternode, they could track transaction histories of the involved addresses. It is not immediately obvious to me how this “hacking” would occur, however.

4. The success rate of PrivateSend is proportional to the number of users: the more users that use it, the more mixing that can be done, so the harder it is to track any individual transaction. But each transaction requires at least 3 users to be able to mix their transaction inputs, whereas a normal BTC transaction only requires 2 users, namely the sender and receiver. There’s also the risk of malicious masternodes, as well as the fact that simply using PrivateSend is suspicious in and of itself, and so may be considered worthy of more scrutiny by financial authorities.