Firo (FIRO) is one of the earliest privacy coins, created by Poramin Insom and his team. It was launched in September 2016 under the name Zcoin, with the token ticker being XZC. Firo is based on Bitcoin's source code and utilizes a GPU-friendly, ASIC-resistant algorithm called the Merkle Tree Function since 2018. The total maximum supply of Firo is 21.4 million, and block rewards are halved every four years.
On January 12, 2021, Firo activated its Lelantus privacy protocol. This protocol increases the anonymity set, hides change amounts, and protects transactional privacy without requiring a trusted setup. Lelantus is the result of Firo's research team, and its innovations are also being used in other privacy projects such as Beam (Lelantus-MW) and Monero (Triptych).
In 2018, Firo's blockchain was used to run the Thailand Democrat Party primary elections. Over 127,000 votes were cast on its blockchain, making it the first large-scale use of blockchain in a political election.
Through the Lelantus protocol, Firo allows you to burn your coins, effectively destroying them and removing their transaction history. Later, you can redeem these burned coins for new coins with no previous transaction history. This process breaks the links between addresses, making transaction graph analysis very difficult.
During the burning process, the coins are destroyed, ceasing to exist, and thereby halting their transaction history. As a result, their traceability is eliminated.
The redemption process involves providing a zero-knowledge proof that you previously burned coins, without revealing which specific coins were burned. The newly redeemed coins appear as fresh coins with no previous transaction history, ensuring no linkage with the original burned coins. Additionally, in Lelantus, input and change amounts are also concealed.
Firo's upcoming privacy protocol, Lelantus Spark, further enhances this concept by hiding all amounts and eliminating the need for redemption.