Overview
The base layer, also known as Layer 1, is Bitcoin's fundamental blockchain protocol. Every transaction recorded on the base layer benefits from the full security of Bitcoin's proof-of-work consensus mechanism. It is the ultimate settlement layer upon which additional protocols and layers are built.
Layered Architecture
Bitcoin's scaling strategy follows a layered approach, similar to the internet's protocol stack:
┌─────────────────────────────────────────┐
│ Layer 3+: Applications & Services │
│ (wallets, exchanges, payment apps) │
├─────────────────────────────────────────┤
│ Layer 2: Lightning Network, sidechains │
│ (fast, cheap, high-volume payments) │
├─────────────────────────────────────────┤
│ Layer 1: Bitcoin Base Layer │
│ (final settlement, maximum security) │
└─────────────────────────────────────────┘
Trade-offs
The base layer prioritizes security and decentralization over raw throughput. With blocks approximately every 10 minutes and a limited block size, the base layer can process a limited number of transactions per second. This is an intentional design choice: keeping the base layer lean ensures that running a full node remains accessible to ordinary users, preserving decentralization.
Settlement Finality
Transactions confirmed on the base layer benefit from probabilistic finality that increases with each additional confirmation. After six confirmations (approximately one hour), a transaction is considered practically irreversible due to the enormous computational cost of reorganizing that many blocks. This strong finality guarantee is what makes the base layer valuable as the foundation for higher-layer protocols.