DEFINITION of 'Coinjoin'

An anonymization strategy that protects the privacy of Bitcoin users when they conduct transactions with each other. Coinjoin requires multiple parties to jointly sign on an agreement to mix their coins when engaging in separate Bitcoin transactions. This makes it harder for outside parties to determine which party or parties was making a particular transaction.

Also known as Coin Mixing.

BREAKING DOWN 'Coinjoin'

Advancements in technology are introducing digital tools that companies can use to better interact with their customers. A rising shift from traditional platforms to digital platforms has also brought about an abundant supply in data from sources like social media, mobile devices, online retail platforms, etc. Due to technology advancements in the areas of gathering, storing, and sharing data, large sets of data are easily shared among companies in every sector and country for little to no costs. The widespread accessibility of data has also brought about concerns over data privacy of individuals and their online transactions. Because every transaction or activity carried out online leaves a digital trail, individuals are opting for more anonymous ways to use the internet and conduct online transactions. The Bitcoin cryptocurrency was introduced to address the issue of privacy concern.

Although conducting transactions with Bitcoin is secure, it is not necessarily anonymous. Every Bitcoin transaction is recorded on a ledger known as a blockchain which is publicly available. Each computer, known as nodes, connected to the Bitcoin network has a copy of the blockchain. The blockchain records information such as addresses of the users and their balances. Due to the transparent nature of Bitcoin transactions, an entity can use the information recorded in the public ledger like the IP address to unveil the identity of the users involved in a transaction, and the type of transaction that was conducted.

Anonymization techniques like Coinjoin were developed to obfuscate the identity of a Bitcoin user involved in a digital transaction. A user that wants to implement coinjoin in his Bitcoin transaction would seek out another user who also wants to mix coins, and they’ll both initiate a joint transaction together. The address a Bitcoin is sent from is referred to as an input. An output refers to the address Bitcoins are sent to. An unwanted surveillance looking through a blockchain can identify a user from a recorded transaction using the input. Coinjoin obfuscates a transaction trail by allowing multiple users combine inputs and outputs from several transactions into one transaction. This way, the blockchain records a single transaction but there is no definite way for an outsider to match the inputs to outputs.

Consider the following transactions made at the same time: A purchases an item from B, C purchases an item from D, and E purchases an item from F. Without Coinjoin, the public blockchain ledger would record three separate transactions for each input-output match. With Coinjoin, only one single transaction is recorded. The ledger would show that bitcoins were paid from A, C, and E addresses to B, D, and F. By masking the deals made by all parties, an observer can’t, with full certainty, determine who sent bitcoins to whom.

Several digital tools that implement Coinjoin in their anonymization procedures include Dark Wallet, JoinMarket, and SharedCoins. These platforms provide an extra level of data masking for users transacting in Bitcoins.

RELATED TERMS
  1. Digital Copy

    A digital copy is a duplicate record of every Bitcoin transaction ...
  2. Silk Road

    A digital platform that was popular for hosting money laundering ...
  3. Bitcoin

    Bitcoin is a digital or virtual currency that uses peer-to-peer ...
  4. Bitcoin Classic

    A fork from Bitcoin Core that proposed increasing the size of ...
  5. SegWit (Segregated Witness)

    SegWit is the process by which blocks on a blockchain are made ...
  6. ZCash

    ZCash is a cryptocurrency with a decentralized blockchain that ...
Related Articles
  1. Tech

    How Bitcoin Can Change the World

    Bitcoin has the potential to not only create savings for the consumer but also to transform global transactions.
  2. Tech

    How Will Bitcoin 2.0 Change The World? (MSFT, OSTK)

    Since Bitcoin's 2009 launch, the decentralized, peer-to-peer digital currency and payment system has garnered worldwide interest.
  3. Tech

    The Rise of 'Private' Cryptocurrencies

    Dash, monero, and other cryptocurrencies with a focus on user privacy are becoming increasingly popular.
  4. Tech

    Countries Where Bitcoin Is Legal & Illegal (DISH, OTSK)

    Many countries do not have consistent laws regulating Bitcoin. It is regulated in most countries, and some have banned it entirely.
  5. Tech

    New Bitcoin Malware Changes Destination Wallets

    Though Bitcoin is designed to guard against fraud, one recent set of incidents points to a way that the currency can be stolen.
  6. Tech

    Speed Is Essential for Bitcoin Platforms

    Why does speed especially matter with Bitcoin technology? It's because Bitcoin platforms using blockchain need to meet the needs of users in times of high volatility.
  7. Tech

    Running a Full Bitcoin Node for Investors

    Running a full bitcoin node has its advantages for investors. Here are two of them.
  8. Investing

    Bitcoin to Form a Third Currency. When Does it End?

    Only weeks after Bitcoin split into two separate entities, the network has decided to add yet another version.
  9. Tech

    How SegWit Made for a More User-Friendly Bitcoin

    The controversial SegWit adoption of Aug. 8 removed signatures from bitcoin blocks, allowing for more room and more speed for transactions.
  10. Tech

    Bitcoin: What Does 2018 Hold In Store?

    The cryptocurrency had a stellar 2017. What factors will influence bitcoin's price movements in 2018?
RELATED FAQS
  1. Is Bitcoin legal in the US?

    Learn about the legality of Bitcoin as a form of payment in the United States, as well as how it is produced and concerns ... Read Answer >>
  2. Why do Bitcoins have value?

    Performing with transactional anonymity, Bitcoin has value as a private digital currency, investment tool and social networking ... Read Answer >>
  3. How are open-market different from closed-market transactions?

    Legal insider transactions can take place in two ways: an open-market transaction or a closed-market transaction. Learn the ... Read Answer >>
Trading Center