Layer 1
The base blockchain layer, such as Ethereum, which processes transactions, maintains consensus, and provides security.
What is Layer 1?
Layer 1 (L1) refers to the base layer or main network of a blockchain ecosystem. It is the foundational blockchain protocol responsible for processing transactions, maintaining its own ledger, and ensuring the security and decentralization of the network. Layer 1 blockchains are self-contained and can operate independently, though they may require additional infrastructure or protocols to enable cross-chain capabilities.
Examples of well-known Layer 1 blockchains include Bitcoin, Ethereum, and Solana. These blockchains handle all aspects of their operation, from transaction execution to consensus to security, within their own network.
Core responsibilities of Layer 1 blockchains:
- Transaction processing: Execute and validate all transactions directly on the main chain
- Consensus mechanism: Maintain agreement on the state of the blockchain among network participants
- Security: Protect the network through economic incentives and cryptographic proofs
- State management: Store and update the complete state of all accounts and smart contracts
- Block production: Create and finalize new blocks containing transaction data
Layer 1 blockchains can serve different functions and have various priorities, such as smart contract platforms, DeFi applications, or data storage. Users typically interact with Layer 1s through decentralized applications (dapps) built on top of them, often using the native network token to pay transaction fees.
Why Layer 1 blockchains matter
Layer 1 blockchains form the foundation of decentralized applications and services. They provide the security, decentralization, and functionality that enable trustless interactions and value transfer without intermediaries. However, standalone Layer 1 blockchains face significant challenges:
Challenges with independent Layer 1s:
- Security burden: Must bootstrap and maintain their own validator set with sufficient stake
- Limited specialization: General-purpose chains can't optimize efficiently for specific use cases
- Scalability constraints: Processing all transactions on a single chain creates bottlenecks
- Isolation: Can't communicate natively with other blockchains without bridges
- Resource intensity: Building and maintaining all infrastructure is demanding for development teams
- Higher costs: Running independent validators and infrastructure increases operational expenses
These challenges have led to the development of Layer 0 protocols and Layer 2 scaling solutions that address these limitations while preserving the benefits of blockchain technology.
Layer 1 blockchains on Polkadot
In the Polkadot ecosystem, Layer 1 blockchains are called rollups (i.e. parachains). These are advanced, application-specific blockchains that connect to Polkadot's Layer 0 infrastructure. Unlike solo Layer 1 blockchains, Polkadot rollups inherit security from the Polkadot Chain while maintaining full sovereignty over their own logic, governance, and features.
How Polkadot rollups work as Layer 1s:
Rollups (i.e., parachains) on Polkadot are separate, fully functioning blockchains with their own state, logic, and execution environment. The primary difference between a rollup and a regular solo blockchain is that the Polkadot Chain (Relay Chain) verifies the state of all rollups connected to it, providing shared security without requiring each rollup to maintain its own validator set.
Rollups operate with their own set of nodes called collators, who collect transactions from users, execute them, and propose new blocks. These blocks are then validated by Polkadot's validators, who ensure the validity of state transitions according to each rollup's specific rules. While rollups choose how blocks are authored and what they contain, the Polkadot Chain provides finality and consensus for those blocks.
Key characteristics of Polkadot rollups:
- Application-specific design: Each rollup can be optimized for particular use cases like DeFi, gaming, identity, or supply chain
- Shared security: All rollups benefit from Polkadot's large validator set without bootstrapping their own
- Native interoperability: Rollups communicate directly through XCM (Cross-Chain Messaging) without external bridges
- Sovereignty: Each rollup maintains its own token, governance, treasury, and community
- Customizable: Full control over the underlying blockchain logic, not just smart contract layer
- Parallel execution: Multiple rollups process transactions simultaneously for greater scalability
Rollups vs solo Layer 1s
The distinction between Polkadot rollups (i.e., parachains) and traditional solo Layer 1 blockchains highlights different architectural approaches:
Standalone Layer 1 blockchains (like Ethereum or Solana):
- Manage their own security through independent validator sets
- Responsible for all aspects of blockchain operation
- Require bridges to communicate with other chains
- General-purpose platforms supporting many applications
- Higher infrastructure and security costs
- Limited by single-chain processing capacity
Polkadot rollups (Layer 1s on Layer 0):
- Inherit security from Polkadot's shared validator set
- Focus on specialized functionality and optimization
- Natively interoperable with other rollups through XCM
- Can be general-purpose or application-specific
- Lower overhead, no need to bootstrap security
- Benefit from parallel processing across multiple rollups
