Glossary
A
Active UID
A UID slot that is considered active within a specific subnet, allowing the associated hotkey to participate as a subnet validator or subnet miner.
Archive Node
A type of public subtensor node that stores the entire blockchain history, allowing for full data access and querying capabilities.
Axon
A module in the Bittensor API that uses the FastAPI library to create and run API servers. Axons receive incoming Synapse objects. Typically, an Axon is the entry point advertised by a subnet miner on the Bittensor blockchain, allowing subnet validators to communicate with the miner.
B
Bicameral Legislature
A two-tier legislative system comprising the Triumvirate and the Senate for proposal approval.
Bittensor Wallet
A digital wallet that holds the core ownership in the Bittensor network and serves as the user's identity technology underlying all operations.
Block
A unit of data in the Bittensor blockchain, containing a collection of transactions and a unique identifier (block hash). A single block is processed every 12 seconds in the Bittensor blockchain.
C
Coldkey
A component of a Bittensor wallet responsible for securely storing funds and performing high-risk operations such as transfers and staking. It is encrypted on the user's device. This is analogous to a private key.
Coldkey-hotkey pair
A combination of two keys, a coldkey for secure storage and high-risk operations, and a hotkey for less secure operations and network interactions.
Commit Reveal
The commit reveal feature is designed to solve the weight-copying problem by giving would-be weight-copiers access only to stale weights. Copying stale weights should result in validators departing from consensus.
See Commit Reveal for details.
Consensus
A measure of a subnet validator's agreement with other validators on the network, calculated based on their trust scores. This is a κ-centered sigmoid of trust, influencing the emission calculation.
D
Delegate
A subnet validator that receives staked TAO tokens from delegators and performs validation tasks in one or more subnets.
Delegate Stake
The amount of TAO staked by the delegate themselves.
Validator Take %
The percentage of emissions a validator takes, of the portion that depends on delegated stake (not including their emissions in proportion to their own self-stake), before the remainder is extracted back to the stakers.
See Emissions.
Delegation
Also known as staking, delegating TAO to a validator (who is thereby the delegate), increases the validator's stake and secure a validator permit.
Dendrite
A client instance used by subnet validators and subnet miners to transmit information to axons on subnet miners and subnet validators. Dendrites communicate with axons using the server-client (Axon-dendrite) protocol.
Deregistration
The process of removing a subnet miner or a subnet validator from the subnet due to poor performance.
E
EdDSA Cryptographic Keypairs
A cryptographic algorithm used to generate public and private key pairs for coldkeys and hotkeys in the Bittensor wallet.
Effective stake
The total staked TAO amount of a delegate, including their own TAO tokens and those delegated by nominators.
Emission
Every block, currency is injected into each subnet in Bittensor, and every tempo (or 360 blocks), it is extracted by participants (miners, validators, stakers, and subnet creators).
Emission is this process of generating and allocating currency to participants. The amount allocated to a given participant over some duration of time is also often referred to as 'their emissions' for the period.
See emissions.
Encrypting the Hotkey
An optional security measure for the hotkey.
External Wallet
A Bittensor wallet created through the Bittensor website or using a tool like subkey, allowing users to use TAO without installing Bittensor.
H
Hotkey
A component of a Bittensor wallet responsible for less secure operations such as signing messages into the network, secure a UID slot in a subnet, running subnet miners and subnet validators in a subnet. It can be encrypted or unencrypted, but is unencrypted by default. The terms "account" and "hotkey" are used synonymously.
Hotkey-Coldkey Pair
Authentication mechanism for delegates and nominators and for delegates participating in the Senate.
I
Immunity Period
A grace period granted to a newly registered subnet miner or subnet validator, during which they will not be deregistered due to performance. Allows a miner or validator new to the subnet to adapt and improve their performance, in order to avoid deregistration once the immunity period expires.
Incentives
A portion of the TAO emission received by the subnet miners when they provide valuable services and compete for UID slots in a subnet.
Incentive Mechanism
A system that drives the behavior of subnet miners and governs consensus among subnet validators in a Bittensor subnet. Each subnet has its own incentive mechanism, which should be designed carefully to promote desired behaviors and penalize undesired ones.
L
Lite Node
A type of public subtensor node that stores limited blockchain data and relies on archive nodes for full historical data.
Local Blockchain
A private blockchain used for developing and testing subnet incentive mechanisms. A local blockchain is not public and is isolated from any Bittensor network.
Local Wallet
A Bittensor wallet created on the user's machine, requiring the installation of Bittensor.
Loss Function
In the context of machine learning, a mathematical function that measures the difference between the predicted output and the ground truth. In Bittensor, incentive mechanisms act as loss functions that steer subnet miners towards desirable outcomes.
M
Mainchain
The primary Bittensor blockchain network, used for production purposes and connected to lite or archive nodes.
Metagraph
A data structure that contains comprehensive information about the current state of a subnet, including detailed information on all the nodes (neurons) such as subnet validator stakes and subnet weights in the subnet. Metagraph aids in calculating emissions.
Miner Deregistration
The process of removing a poor-performing subnet miner from a UID slot, making room for a newly registered miner.
See Mining in Bittensor: Miner Deregistration
Mnemonic
A sequence of words used to regenerate keys, in case of loss, and restore coldkeys and hotkeys in the Bittensor wallet.
N
NaCl Format
A secure encryption format, using the NaCl library, used for updating legacy Bittensor wallets to improve security.
Netuid
A unique identifier assigned to a subnet within the Bittensor network.
Neuron
The basic computing node in a Bittensor subnet, representing a node in a neural network. Neurons can be either subnet validators or subnet miners.
Nominate
The process of a delegate registering themselves as a candidate for others to stake their $TAO to.
Nominator
Another term for a delegator. A subnet validator who nominates their own hotkey as a delegate, allowing others to delegate their TAO to the nominator's hotkey.
Nominator (Delegator)
A TAO holder who delegates their stake.
O
Objective Function
In the context of machine learning and subnet operations, this refers to the goal that the subnet is continuously optimizing for, through its incentive mechanism.
P
Private Key
A private component of the cryptographic key pair, crucial for securing and authorizing transactions and operations within the Bittensor network.
Proposal
A suggestion or plan put forward by the Triumvirate for the Senate to vote on.
Proposal hash
A unique identifier for a proposal used in the voting process.
Public Key
A cryptographic key that is publicly available and used for verifying signatures, encrypting messages, and identifying accounts in the Bittensor network. This is the publicly shareable part of the cryptographic key pair associated with both the coldkey and hotkey, allowing others to securely interact with the wallet.
Public Subtensor
A publicly accessible node in the Bittensor network that can be run as a lite node or an archive node and synchronized with either the mainchain or testchain.
R
RAO
A denomination of TAO, representing one billionth (10-9) of a TAO.
Rank
A measure of a subnet miner's performance relative to other subnet miners in the same subnet, calculated based on the subnet miner's trust and incentive scores. This is the sum of weighted stake, contributing to the emission process.
Recycling, burning, and locking
"Recycling TAO" means that this TAO is put back into the Bittensor emissions system. Instead of minting new TAO this recycled TAO that is in the recycle bin will be used again in the new emissions.
This happens in two cases:
- When you register either as a subnet validator or a subnet miner and get a
UIDin return, the registration cost TAO you pay is recycled. - Emissions are recycled for those subnets that have registration turned off or paused.
When TAO is burned it is permanently removed from circulation, reducing total supply.
Locked TAO is neither recycled nor burned, but held unspent, without the ability to move it until it is unlocked. The cost for subnet registration is locked and returned if the subnet is deregistered.
Regenerating a Key
The process of recreating a lost or deleted coldkey or hotkey using the associated mnemonic.
Register
The process of registering keys with a subnet and purchasing a UID slot.
S
SS58 Encoded
A compact representation of public keys corresponding to the wallet's coldkey and hotkey, used as wallet addresses for secure TAO transfers.
Senate
A group of elected delegates formed from the top K delegate hotkeys, responsible for approving or disapproving proposals made by the Triumvirate.
Stake
The amount of currency tokens delegated to a validator UID in a subnet. Includes both self-stake (from the validator's own cold-key) and stake delegated from others.
Stake determines a validator's weight in consensus as well as their emissions.
Staking
The process of attaching TAO to a hotkey, i.e., locking TAO to a hotkey, to participate as a subnet validator, and to secure a validator permit.
Subnet
A Bittensor subnet is an incentive-based competition market that produces a specific kind of digital commodity. It consists of a community of miners that produce the commodity, and a community of validators that measures the miners' work to ensure its quality.
Subnet Incentive Mechanism
The framework that governs the behavior of subnet miners and ensures consensus among subnet validators by promoting desirable actions and penalizing undesired ones.
Subnet Miner
The task-performing entity within a Bittensor subnet. A subnet miner is a type of node in a Bittensor subnet that is connected only to subnet validators. Subnet miners are isolated from the external world and communicate bidirectionally with subnet validators. A subnet miner is responsible for performing tasks given to them by the subnet validators in that subnet.
Subnet Creator
The individual or entity responsible for defining the specific digital task to be performed by subnet miners, implementing an incentive mechanism, and providing sufficient documentation for participation in the subnet.
Subnet Protocol
A unique set of rules defining interactions between subnet validators and miners, including how tasks are queried and responses are provided.
Subnet scoring model
A component of the incentive mechanism that defines how subnet miners' responses are evaluated, aiming to align subnet miner behavior with the subnet's goals and user preferences. It is a mathematical object that converts miner responses into numerical scores, enabling continuous improvement and competition among miners.
Subnet Task
A key component of any incentive mechanism that defines the work the subnet miners will perform. The task should be chosen to maximize subnet miner effectiveness at the intended use case for the subnet.
Subnet Validator
A type of node in a subnet that creates tasks, evaluates the performance of subnet miners and sets weights based on their output. A subnet validator is connected only to subnet miners and to the external world. Subnet validators receive inputs from the external world and communicate bidirectionally with subnet miners.
Subnet Weights
The importance assigned to each subnet determined by relative price among subnets and used to determine the percentage emissions to subnets.
Subtensor
Subtensor is Bittensor's layer 1 blockchain based on substrate (now PolkadotSDK). This serves Bittensor as a system of record for transactions and rankings, operates Yuma Consensus, and emits liquidity to participants to incentivize their participation in network activities.
The Bittensor SDK offers the bittensor.core.subtensor and bittensor.core.async_subtensor modules to handle Subtensor blockchain interactions.
Sudo
A privileged key for administrative actions, replaced by governance protocol for enhanced security.
Synapse
A data object used by subnet validators and subnet miners as the main vehicle to exchange information. Synapse objects are based on the BaseModel of the Pydantic data validation library.
T
TAO (τ)
The cryptocurrency of the Bittensor network, used to incentivize participation in network activities (mining, validation, subnet creation and management). A single TAO is newly created (i.e., minted) every 12 seconds on the Bittensor blockchain.
Tempo
A 360-block period during which the Yuma Consensus calculates emissions to subnet participants based on the latest available ranking weight matrix. A single block is processed every 12 seconds, hence a 360-block tempo occurs every 4320 seconds or 72 minutes.
Transfer
The process of sending TAO tokens from one wallet address to another in the Bittensor network.
Triumvirate
A group of three Opentensor Foundation employees responsible for creating proposals.
Trust
A measure of a subnet miner's reputation and reliability, calculated based on the consensus of subnet validators.
Trust (T)
A measure of the confidence in a subnet based on the stakes that set non-zero weights.
U
UID Slot
A position occupied by a subnet miner or subnet validator within a subnet, identified by a unique UID. The UID is assigned to a hotkey when it is registered in a subnet, allowing the hotkey to participate as a subnet validator or subnet miner.
V
VPermit
Validator permits held by the delegate for specific subnets.
Validator Module
The software component that subnet validators run to perform their subnet validation operations within a subnet.
W
Wallet Address
A unique identifier derived from the public key, used as a destination for sending and receiving TAO tokens in the Bittensor network.
Wallet Location
The directory path where the generated Bittensor wallets are stored locally on the user's machine.
Weight Matrix
A matrix formed from the ranking weight vectors of all subnet validators in a subnet, used as input for the Yuma Consensus module to calculate emissions to that subnet.
Weight Vector
A vector maintained by each subnet validator, with each element representing the weight assigned to a subnet miner based on its performance.
The ranking weight vectors for each subnet are transmitted to the blockchain, where they combine to form the weight matrix that is input for Yuma Consensus.
Y
Yuma Consensus
The consensus mechanism in the Bittensor blockchain that computes emissions to participants.
See Yuma Consensus