
A mainchain is the primary network layer in a blockchain ecosystem, responsible for processing and validating all transactions and maintaining the security and consensus mechanism of the entire network. As the core foundation of blockchain architecture, the mainchain ensures the finality and irreversibility of transactions, providing security guarantees for applications and sidechains running on top of it. In multi-layer blockchain solutions, the mainchain typically handles the most critical settlement functions while delegating more complex computation and application logic to layer-two networks or sidechains to achieve greater scalability.
The concept of a mainchain originated from early blockchain systems like Bitcoin with their single-chain structure. As blockchain technology evolved and faced scalability and performance challenges, developers began exploring multi-layered architectural solutions. The concept of a mainchain as a base layer emerged, particularly gaining recognition after Ethereum proposed sharding technology and layer-two scaling solutions. Mainchains, along with concepts like sidechains and layer-two networks, now constitute the modern blockchain scaling ecosystem. Mainchains maintain core security properties and finality, while auxiliary chains provide higher transaction throughput and application flexibility.
Mainchains operate based on these core mechanisms:
Consensus mechanism: Mainchains employ consensus algorithms like Proof of Work (PoW) or Proof of Stake (PoS) to ensure network participants agree on the transaction history.
Block production: Validator nodes collect and verify pending transactions, package them into blocks, and add them to the chain through the consensus mechanism.
Security guarantees: Mainchains ensure network security through economic incentives and cryptographic mechanisms that make tampering with historical transactions economically unfeasible.
Cross-chain communication: Mainchains interact with sidechains or layer-two networks through cross-chain bridges, state channels, or relay mechanisms to enable secure transfer of assets and information.
In multi-layered architectures, mainchains focus on validation and settlement functions, maintaining lower transaction frequency but ensuring the highest security levels, while offloading high-frequency transactions and complex computations to auxiliary network layers.
Scalability bottlenecks: Mainchains typically face throughput limitations, potentially leading to congestion and high transaction fees as network usage increases.
Governance challenges: Protocol upgrades on mainchains require broad consensus, which can lead to community splits and hard forks.
Centralization tendencies: Some consensus mechanisms may exhibit validator centralization over time, threatening the network's decentralization properties.
Security trade-offs: Interoperability between mainchains and auxiliary layers may introduce new security vulnerabilities and attack vectors.
Technical debt: Early design decisions may limit future evolution capabilities, making it difficult for mainchains to adapt to emerging technological developments.
Coordination complexity: In multi-layered architectures, mainchains must effectively coordinate with different layers to ensure overall system security and consistency.
Mainchains must balance security, decentralization, and scalability—a challenge known as the "blockchain trilemma."
Mainchains serve as the core infrastructure of blockchain ecosystems, critical to the healthy development of the entire crypto economy. They not only provide a secure transaction settlement layer but also lay the foundation for innovative scaling solutions. As blockchain technology continues to evolve, mainchains will adapt to new technological paradigms while maintaining their core value as trustless, decentralized ledgers. The synergistic development of mainchains and various scaling solutions is paving the way for mainstream blockchain adoption, enabling support for broader use cases and higher transaction throughput without sacrificing the core properties of decentralization and security.


