Lightning Network (Payment Channels)
TL;DR
The Lightning Network enables instant Bitcoin payments through off-chain payment channels, settling only the net result on the Timechain.
What Is It?
The Lightning Network is a Layer 2 scaling solution built on top of Bitcoin. It uses Payment Channels to allow users to transact instantly and cheaply without settling every transaction on the main chain.
How It Works
- Opening: Two parties lock funds into a multisig address on the main chain. This is the “channel.”
- Transacting: They can update the balance of who owns what within that channel instantly, millions of times. These updates are valid Bitcoin transactions that are not broadcasted yet.
- Closing: Either party can close the channel, broadcasting the final state to the main chain. The miners only see the net result.
Why Does It Matter?
- Instant Settlement: No need to wait 10 minutes for confirmations.
- Microtransactions: Fees are negligible, enabling streaming payments (e.g., pay per second of video).
- Privacy: Intermediate hops in a payment route (onion routing) don’t know who the sender or receiver is.
Evolution
- HTLCs (Hash Time Locked Contracts): The current standard for routing payments.
- PTLCs (Point Time Locked Contracts): An upgrade (using Schnorr signatures) that improves privacy by making payments decorrelatable.