Below are a list of terms and their definitions that are used throughout the Tari code and documentation. Let's use this glossary to disambiguate ideas, and work towards a ubiquitous language for this project.
This is a full history base node. It will keep a complete history of every transaction ever received and it will not implement pruning.
An entity that creates digital assets on the Tari DAN. The Asset Issuer will specify the parameters of the contract template that defines the rules that govern the asset and the number and nature of its constituent tokens on issuance. The Asset Issuer will, generally, be the initial owner of the tokens.
A participant that acts maliciously or negligently to the detriment of the network or another participant.
A full Tari node running on the base layer. It's primary role is validating and propagating Tari coin transactions and blocks to the rest of the network.
A collection transactions and associated metadata recorded as a single entity in the Tari blockchain. The ordering of Tari transactions is set purely by the block height of the block they are recorded in.
A data structure that validates the information contained in a block.
The amount of Tari created by the coinbase transaction in every block. The block reward is set by the emission schedule.
A sequence of tari blocks. Each block contains a hash of the previous valid block. Thus the blocks form a chain with the property that changing anything in a block other than the head block requires rewriting the entire blockchain from that point on.
The complete state of the blockchain at a specific block height. This means a pruned utxo set, a complete set of kernels and headers up to that block height from the genesis block.
A strategy for propagating messages amongst nodes in a peer-to-peer network. Example implementations of
BroadcastStrategy include the Gossip protocol, Dandelion and flood fill.
A hash of the state of a Digital Asset that is recorded on the base layer.
A strategy for an Asset Issuer to select candidates for the committee from the available registered Validator Nodes who responded to the nomination call for that asset.
The approach that will be taken for a committee to reach consensus on the validity of instructions that are performed on a given Digital Asset.
A commitment is a cryptographic primitive that allows one to commit to a chosen value while keeping it hidden from others, with the ability to reveal the committed value later. Commitments are designed so that one cannot change the value or statement after they have committed to it.
A Communication Node is either a Validator Node or Base Node that is part of the Tari communication network. It maintains the network and is responsible for forwarding and propagating joining requests, discovery requests and data messages on the communication network.
A Communication Client is a Wallet or Asset Manager that makes use of the Tari communication network to send joining and discovery requests. A Communication Client does not maintain the communication network and is not responsible for forwarding or propagating any requests or data messages.
Digital assets (DAs) are the sets or collections of native digital tokens (both fungible and non-fungible) that are created by asset issuers on the Tari 2nd layer. For example, a promoter might create a DA for a music concert event. The event is the digital asset, and the tickets for the event are digital asset tokens.
The Tari second layer. All digital asset interactions are managed on the Tari Digital Assets Network (DAN). These interactions (defined in instructions) are processed and validated by Validator Nodes.
A DigitalAssetTemplate is one of a set of contract types supported by the DAN. These contracts are non-turing complete and consist of rigid rule-sets with parameters that can be set by Asset Issuers.
Digital asset tokens (or often, just "tokens") are the finite set of digital entities associated with a given digital asset. Depending on the DA created, tokens can represent tickets, in-game items, collectibles or loyalty points. They are bound to the digital asset that created them.
A time locked contract that only pays out after a certain criteria has been met or refunds the originator if a certain period has expired.
An explicit formula as a function of the block height, h, that determines the block reward for the hth block.
Instructions are the digital asset network equivalent of transactions. Instructions are issued by asset issuers and client applications and are relayed by the DAN to the validator nodes that are managing the associated digital asset.
The mempool consists of the transaction pool, pending pool, orphan pool and reorg pool, and is responsible for managing unconfirmed transactions that have not yet been included in the longest proof-of-work chain. Miners usually draw verified transactions from the mempool to build up transaction blocks.
Mimblewimble is a privacy-centric cryptocurrency protocol. It was dropped in the Bitcoin Developers chatroom by an anonymous author and has since been refined by several authors, including Andrew Poelstra.
A Mining Server is responsible for constructing new blocks by bundling transactions from the mempool of a connected Base Node. It also distributes Proof-of-Work tasks to Mining Workers and verifies PoW solutions.
A Mining Worker is responsible for performing Proof-of-Work tasks received from its parent Mining Server.
Multi-signatures (Multisigs) are also known as N-of-M signatures, this means that a minimum of N number of the M peers need to agree before a transaction can be spent. N and M can be equal; which is a special case and is often referred to as an N-of-N Multisig.
A node ID is a unique identifier that specifies the location of a communication node or communication client in the Tari communication network. The node ID can either be obtained from registration on the Base Layer or can be derived from the public identification key of a communication node or communication client.
This is a local setting for each node to help reduce syncing time and bandwidth. This is the number of blocks from the chain tip beyond which a chain will be pruned.
An asset runs in public nomination mode when the Asset Issuer broadcasts a call for nominations to the network and VNs from the network nominate themselves as candidates to become members of the committee for the asset. The Asset Issuer will then employ the CommitteeSelectionStrategy to select the committee from the list of available candidates.
An amount of tari coin that is locked up on the base layer when a Validator Node is registered. In order to make Sybil attacks expensive and to provide an authorative base layer registry of validator nodes they will need to lock up a amount of Tari Coin on the Base Layer using a registration transaction to begin acting as a VN on the DAN.
The minimum amount of time that a VN registration lasts, the Registration Deposit can only be released after this minimum period has elapsed.
The reorg pool is part of the mempool and stores all transactions that have recently been included in blocks in case a blockchain reorganization occurs and the transactions need to be restored to the transaction pool.
A private spending key is a private key that permits spending of a UTXO. It is also sometimes referred to as a Blinding Factor, since is Tari (and Mimblewimble) outputs, the value of a UTXO is blinded by the spending key:
$$ C = v.H + k.G $$
The public key, \(P = k.G\) is known as the public spending key.
The current synchronisation state of a Base Node. This can either be
new- The blockchain state is empty and is waiting for synchronisation to begin.
synchronising- The blockchain state is in the process of synchronising with the rest of the network.
synchronised- The blockchain state has synchronised with the rest of the network and is in a position to validate transactions.
The generalised approach for a Base Node to obtain the current state of the blockchain from the peer-to-peer network. Specific implementations may differ based on different trade-offs and constraints with respect to bandwidth, local network conditions etc.
A permissioned Validator Node nominated by an Asset Issuer that will form part of the committee for that Digital Asset.
A Tari Token Wallet is responsible for managing Digital assets and Tokens, and for constructing and negotiating instructions for transferring and receiving Assets and Tokens on the Digital Asset Network.
An unspent transaction output (UTXO) is a discrete number of Tari that are available to be spent. The sum of all UTXOs represents all the Tari currently in circulation. In addition, the sum of all UTXO values equals the sum of the block rewards for all blocks up to the current block height.
Transactions or blocks are
unvalidated when first received by a Base Node. After validation, they are either
Validated transactions can be added to the mempool and propagated to peers.
Validated blocks are added to the blockchain and propagated to peers.
This document is subject to the disclaimer.