Every term, in plain words
Short definitions of the words used in the lessons. Each one links to the concept where it is explained with live data.
Betanet
eCash's rehearsal network, started from a snapshot of Bitcoin at block 967,680, used to try drivechains before eCash's mainnet.
Learn it in “What is a drivechain?” →Bid
The amount a BMM Request offers the L1 miner.
Learn it in “Blind merged mining” →Blind merged mining (BMM)
BIP301's way for L1 miners to earn sidechain fees without running sidechain software.
Learn it in “Blind merged mining” →Block
A batch of transactions added to the chain by a miner, on average every ten minutes.
Learn it in “Blocks: the heartbeat” →Block hash
A block's unique fingerprint. Each block also records the hash of its parent, which links the chain together.
Learn it in “Blocks: the heartbeat” →BMM Accept (M7)
A miner's coinbase commitment to one sidechain block hash per slot.
Learn it in “Blind merged mining” →BMM Request (M8)
A sidechain user's L1 transaction offering miners a payment if the block commits to their sidechain block hash.
Learn it in “Blind merged mining” →Coinbase transaction
The first transaction in a block, written by the miner. BIP300 and BIP301 place the miners' messages and votes there.
Learn it in “Creating a sidechain” →Coverage
Which blocks the monitor has actually recorded. Without coverage, a missing record does not mean nothing happened.
Learn it in “How we know” →CTIP (treasury output)
The single unspent output holding all of a sidechain's locked coins. Every deposit or withdrawal replaces it with a new one.
Learn it in “Deposits and the treasury” →Declaration
What a proposal says about the sidechain: title, description and two hashes intended to identify its software.
Learn it in “Slots and sidechains” →eCash (ECX)
A hard fork of Bitcoin, associated with Paul Sztorc and LayerTwo Labs, that activates drivechains (BIP300 and BIP301). It is a different coin and network from eCash (XEC).
Learn it in “What is a drivechain?” →Enforcer
The program that checks the BIP300/301 rules alongside the L1 node. The Observatory reads its official API.
Learn it in “How we know” →Evidence
The exact record the monitor captured from the enforcer or node, kept so anyone can check what a page shows.
Learn it in “How we know” →Hashrate escrow
BIP300's name for a sidechain's locked coins: miners, voting with the blocks they find, decide when coins may leave.
Learn it in “What is a drivechain?” →Height
A block's position in the chain: the number of blocks before it.
Learn it in “Blocks: the heartbeat” →L1 (mainchain)
The base blockchain. On this site it is eCash Betanet.
Learn it in “What is a drivechain?” →M1 · Propose sidechain
A coinbase message that proposes a new sidechain for a slot.
Learn it in “Creating a sidechain” →M2 · ACK proposal
A coinbase message in which a miner votes for a pending sidechain proposal.
Learn it in “Creating a sidechain” →M3 · Propose bundle
A coinbase message that puts a withdrawal bundle up for a vote. It counts as the first vote.
Learn it in “Withdrawals by miner vote” →M4 · ACK bundles
A coinbase message with each block's withdrawal votes: upvote one bundle per sidechain, abstain, or raise an alarm.
Learn it in “Withdrawals by miner vote” →M5 · Deposit
An L1 transaction that spends the treasury output and creates a new one holding more coins.
Learn it in “Deposits and the treasury” →M6 · Withdraw
The L1 transaction that pays out an approved bundle and returns the rest of the coins to a new treasury output.
Learn it in “Withdrawals by miner vote” →M6 id
The identifier miners vote on for a bundle: the id of a "blinded" copy of the withdrawal transaction without its treasury input, which usually does not exist yet when voting starts.
Learn it in “Withdrawals by miner vote” →Observed in a block
A fact the official sources reported for a specific L1 block.
Learn it in “How we know” →OP_DRIVECHAIN
The opcode that marks a treasury output. BIP300 uses OP_NOP5; Betanet uses OP_NOP8.
Learn it in “Deposits and the treasury” →Read at a tip
A reading of current state taken while the chain tip stayed the same before and after. It is not tied to one block and does not prove an atomic snapshot.
Learn it in “How we know” →Reorganization (reorg)
When the network switches to a competing branch with more work, so some recent blocks stop being part of the chain.
Learn it in “Blocks: the heartbeat” →Sidechain (L2)
A separate blockchain whose coins are locked on the L1 and released only by a slow miner vote. It has its own software and rules.
Learn it in “What is a drivechain?” →Sidechain instance
One specific sidechain in a slot, identified by its slot, proposal, activation height and declaration hash.
Learn it in “Slots and sidechains” →Slot
One of 256 numbered places (0–255) a sidechain can occupy. A slot can host different sidechains over time.
Learn it in “Slots and sidechains” →Threshold
The number of votes that must be exceeded, within a maximum age, for a proposal or withdrawal to pass. Betanet reports its own values.
Learn it in “Creating a sidechain” →Unknown
The data is missing, conflicting or was read while the chain moved. The Observatory never fills such gaps by guessing.
Learn it in “How we know” →Withdrawal bundle
Many withdrawals from one sidechain combined into one L1 transaction. It pays everyone or no one.
Learn it in “Withdrawals by miner vote” →