| Transaction Name | Description | Nodes | Condition(s) |
|---|---|---|---|
| Setup Tx | Spend from ‘Funding’ UTXO to 'Setup' UTXO when a new channel is funded. Node A will not sign this until they have a signed Refund Tx from Node B. | Sender: A
Receiver: B |
A & B sign |
| Refund Tx | Spend from ‘Setup’ UTXO to ‘Funding’ UTXOs after some delay. Specifically created when a channel is first created. | Sender: A
Receiver: B |
A & B sign; Valid after a delay relative to when the transaction it spends from is committed. |
| Update Tx | Spend from ‘Setup’ or older ‘Update’ UTXO to 'Update' UTXO with newer state. Occurs immediately when this transaction is committed. | Sender: A
Receiver: B |
A & B sign; Current channel state > channel state of transaction it spends from |
| Settlement Tx | Spend from ‘Setup’ or ‘Update’ UTXO to final single signature ‘Funding’ UTXOs after some delay. Encodes a specific balance division. |
Sender: A
Destination: D |
A & B sign;
Valid after a delay relative to when the transaction it spends from is committed; D signs hash of Message |
| Close Tx | Unconditionally move funds from the most recent ‘Update’ UTXO to a set of balances at final single key ‘Funding’ UTXOs. | Sender: A
Receiver: B |
A & B sign
|