Lightning Network
The Lightning Network is a layer-2 payment protocol built on top of Bitcoin that enables fast, low-cost transactions through a network of bidirectional payment channels. It allows millions of transactions per second without recording each one individually on the blockchain.
How It Works
The Lightning Network works by creating payment channels between two parties. To open a channel, participants create an on-chain Bitcoin transaction that locks funds into a 2-of-2 multisig address. Once the channel is open, they can transact back and forth by exchanging signed but unbroadcast transactions that update the balance between them. Only the opening and closing transactions are recorded on the blockchain.
Payments can be routed across multiple channels, enabling you to pay anyone on the network even without a direct channel. If Alice has a channel with Bob, and Bob has a channel with Carol, Alice can pay Carol through Bob. Hash Time-Locked Contracts (HTLCs) ensure that intermediary routing nodes cannot steal funds — either the payment completes atomically across all hops or it fails entirely.
Lightning trades some of Bitcoin's base-layer security properties for speed and cost efficiency. Channels require at least one party to monitor for fraud attempts (broadcasting old channel states). Running your own Lightning node is important for security and sovereignty. Lightning is ideal for smaller, everyday payments, while the base layer remains the settlement layer for larger, high-security transactions.
Key Points
- Layer-2 protocol enabling near-instant, low-cost Bitcoin payments
- Payment channels use on-chain multisig for opening and closing
- Payments route across the network via Hash Time-Locked Contracts (HTLCs)
- Requires active channel monitoring to prevent fraud
- Best suited for smaller payments — base layer remains the settlement layer