#explain-card A [[Layer 1]] (L1) network refers to a [[Base|base]] blockchain protocol, such as [[Bitcoin]] or [[Ethereum]]. These are the primary networks that form the foundational layer of their respective ecosystems. They are responsible for processing and validating transactions, as well as maintaining the integrity and security of the distributed [[Ledger|ledger]]. Key characteristics of Layer 1 blockchains typically include their own [[Consensus|consensus]] mechanism (e.g., [[Proof of work]] or [[Proof of stake]]), a native cryptocurrency, and the ability to support the creation of decentralized applications ([[DApp|dApps]]) and other blockchain-based solutions. The core functions of a Layer 1 network are to provide security, decentralization, and data availability. However, many Layer 1 networks face challenges related to scalability, often referred to as the blockchain trilemma, which involves balancing security, decentralization, and scalability. Examples of prominent Layer 1 blockchains include: - Bitcoin - Ethereum - [[Solana]] - [[Avalanche]] To address scalability limitations, [[Layer 2]] solutions are often built on top of Layer 1 networks. These Layer 2 solutions handle transactions off the main chain, thereby reducing congestion and transaction fees on the Layer 1, while still relying on the underlying Layer 1 for security and finality.