Zerocoin is a privacy protocol proposed in 2013 by Johns Hopkins University professor Matthew D. Green and his graduate students, Ian Miers and Christina Garman.
In May 2013, Matthew D. Green and his graduate students (Ian Miers and Christina Garman) proposed the Zerocoin protocol where cryptocurrency transactions can be anonymized without going through a trusted third-party, by which a coin is destroyed then minted again to erase its history.
[6] In January 2018, an academic paper partially funded by Zcoin was published on replacing Proof-of-work system with memory intensive Merkle tree proof algorithm in ensuring more equitable mining among ordinary users.
[19] In the late 2014, Poramin Insom, a student in Masters in Security Informatics from Johns Hopkins University wrote a paper on implementing the zerocoin protocol into a cryptocurrency with Matthew Green as faculty member.
[21] On 20 February 2017, a malicious coding attack on Zerocoin protocol created 370,000 fake tokens which perpetrators sold for over 400 Bitcoins ($440,000).
Zcoin team announced that a single-symbol error in a piece of code "allowed an attacker to create Zerocoin spend transactions without a corresponding mint".
[23] Unlike Ethereum during the DAO event, developers have opted not to destroy any coins or attempt to reverse what happened with the newly generated ones.
[24] In September 2018, Zcoin introduced the Dandelion protocol that hides the origin IP address of a sender without using a The Onion Router (Tor) or Virtual Private Network (VPN).
[citation needed] Depending on the specific implementation, Zerocoin requires two very large prime numbers to generate a parameter which cannot be easily factored.