3. Tokenization standard
3.0 Tokenization Standards #
In Mintlayer, issuing a token does not require a smart contract; instead, it is a built-in feature of the protocol. A token is represented by a TokenId in a Output.
pub enum OutputValue {
Coin(Amount), // ML Token is build-in
TokenV1(TokenId, Amount), // Any other token must specify a TokenId
}
A TokenId is defined as:
pub enum Token {}
pub struct Id<T> {
hash: H256,
}
pub type TokenId = Id<Token>;
This essentially means that within the system, a token exists as a collection of Outputs, each owned by different parties.
3.1 Fungible Tokens (MLS01) #
Standard fungible tokens, serving a similar role to Ethereum’s ERC-20, are defined by the MLS-01 standard on Mintlayer. MLS-01 represents the most basic form of token on the chain. Due to the simplicity of Mintlayer’s UTXO architecture, creating these tokens is significantly more straightforward than on competing chains, where a contract written in a language like Solidity is required. Any token adhering to the MLS-01 standard should be compatible with all Mintlayer wallets.
An MLS-01 token has several associated features, including a ticker, an issuance amount, a number of decimals for the issuance amount, and a metadata URI and a replaceble authority. A token can also support features such as increasing the circulating supply or preventing further increases in the circulating supply.
pub struct TokenIssuanceV1 {
pub token_ticker: Vec<u8>,
pub number_of_decimals: u8,
pub metadata_uri: Vec<u8>,
pub total_supply: TokenTotalSupply,
pub authority: Destination,
pub is_freezable: IsTokenFreezable,
}
3.2 Non Fungible Tokens NFT (MLS03) #
Non-fungible tokens, often referred to as NFTs, are implemented through the MLS-03 standard on Mintlayer. Similar to NFTs on other blockchains, they represent unique tokens. They function in a manner akin to MLS-01 tokens, with the key difference being that they do not require handling a supply, as each NFT is one-of-a-kind. However, NFTs do possess additional data attributes: a creator, a name, a description, an icon, a media hash, and a media URI.
pub struct Metadata {
pub creator: Option<TokenCreator>,
pub name: Vec<u8>,
pub description: Vec<u8>,
pub ticker: Vec<u8>,
pub icon_uri: DataOrNoVec<u8>,
pub additional_metadata_uri: DataOrNoVec<u8>,
pub media_uri: DataOrNoVec<u8>,
pub media_hash: Vec<u8>,
}
3.3 Confidential Token (MLS02) #
The MLS-02 standard represents a similar token to MLS-01 but with the added benefit and complexity of being a privacy-focused token that allows for zero-knowledge based private transactions.
NOTE: This feature is currently under development and will be part of a future upgrade. Please note that technical details are subject to change {.is-danger}
