Zcoin uses the Burn-and-Redeem privacy model, offering an alternative to Coinjoin

The Zcoin coin privacy project recently launched the Lelantus privacy protocol on its testnet. Lelantus allows confidential and anonymous blockchain transactions with short verification times.

Using a burn-and-redeem model, users are able to shred arbitrary amounts of coins and redeem new ones, so that there is no previous transaction history associated with them.

Burn and redeem

The burn-and-redeem model is an alternative to other privacy methods such as coinjoins or using other people's transactions Investors as covers. Zcoin, allows you to destroy your coins and add them to a pool that contains all the coins that other users have destroyed, and then recover them later.

“At any time in the future, you can send cryptographic proof that you have destroyed / burned coins without revealing which coin it was,” said Reuben Yap, Steward of the Zcoin project. "This trial, once accepted, will allow you to redeem coins that have no previous transactions or links."

The new Lelantus functions of Zcoin

Lelantus uses a one-out-of-many proof cryptographic concept, which proves that you are one of many people who burned coins, without revealing which coins you actually burned.

It also allows users to redeem partial amounts of coins when they want. Lelatnus also doesn't require any trusted setup. In cryptographic terms, a trusted setup creates a cryptographic system by generating some initial parameters which will later be destroyed.

It is called this because you need to trust who creates these settings and that the aforementioned parameters will actually be destroyed. "A trusted setup compromised in a zero-knowledge-proof mechanism would allow someone to falsify evidence, which implies that coins could be created out of thin air leading to hyperinflation," Yap said. "In private currencies where the amounts are obscured, such inflation can also remain unnoticed."

Lelantus 2.0 coming?

Lelantus' mainnet launch is currently scheduled for about a month, depending on feedback from the testnet. "We are already working on Lelantus 2.0 or Aura, which allows you to transfer the right of redemption to someone else, keeping the amounts hidden," added Yap.

"You don't have to redeem the coins yourself, but you can transfer that right that offers the highest level of privacy." Zcoin was launched in 2016 and is based on the Zerocoin protocol, which used a zero-knowledge-proof mechanism to secure user transactions.

It is not to be confused with Zcash, which is based on Zerocash documents. Although the Zerocoin and Zerocash code share some of the authors and use a zero-knowledge-proof mechanism, they are based on different cryptography, the Zcoin team said.