A Lightning Network node is your “gateway” into the Lightning network ecosystem. To be able to do anything on the lightning network, you need to be running a node or use someone else's node through a custodial wallet. This will give you access to fast, cheap, and private payments on top of bitcoin’s blockchain.
A Lightning Network node has two responsibilities.
- Monitor the underlying bitcoin blockchain
- Interact with other Lightning Network nodes to transact money
Every Lightning Network node must monitor the bitcoin blockchain. If the Lightning Network node does not do this properly, funds can be stolen from you.
A Lightning Network node also interacts with other nodes on the peer-to-peer network. When talking about Lighting, you need to remember there are two separate networks we are interacting with.
- The bitcoin blockchain’s peer-to-peer network
- The Lightning peer-to-peer network
The Lightning p2p network is where money is transacted on the Lightning network. It is a Lightning Network node’s responsibility to exchange money with other Lightning nodes. This is done through Lightning channels which are created between nodes.
Each Lightning network node is responsible for keeping track of who has what in the channel. When you want to leave a lightning network channel, you cash out to the blockchain.