What Are Sidechains?

What Are Sidechains?

Sidechains are separate blockchains that are linked to the main blockchain through a two-way bridge. This connection allows assets to be transferred between them. Sidechains can operate independently with their own unique consensus mechanisms and block parameters. This enables efficient processing of transactions and customization for specific purposes. Sidechains offer scalability, flexibility, and EVM compatibility. However, using sidechains also has trade-offs, including potential decentralization challenges and the need for robust security measures to ensure the safety of the transactions.


The concept of sidechains arose from the growing need for scalability and efficiency within blockchain technology. It was first proposed in October 2014 in a seminal paper titled "Enabling Blockchain Innovations with Pegged Sidechains," authored by Adam Back and a team of prominent cryptographers and Bitcoin developers, including Matt Corallo, Luke Dashjr, Andrew Poelstra, and Pieter Wuille. But what precisely are sidechains, and how do they influence the progression of blockchain ecosystems?

What Are Sidechains?

A sidechain is a blockchain that operates separately from the main blockchain, also known as the main chain. To facilitate the transfer of digital assets or tokens between the two, a two-way bridge is typically established, allowing for seamless exchange.

How Sidechains Operate

Sidechains distinguish themselves through their self-governance. Unlike the main chain, they possess the flexibility to implement bespoke consensus mechanisms and block configurations suited to their specific objectives. This autonomy enables efficient transaction processing, yielding benefits like expedited confirmation durations and reduced transaction fees.

Various consensus algorithms are employed on sidechains, spanning from Proof-of-Authority to Delegated Proof-of-Stake. Validators within the sidechain ecosystem assume pivotal roles in transaction validation, block generation, and chain security maintenance.

Moreover, sidechains often deviate from the primary chain concerning block parameters. While the main blockchain imposes constraints on block sizes and times, sidechains can tailor these parameters to enhance throughput. Nonetheless, such adjustments entail trade-offs; looser block parameters may compromise decentralization by favoring a limited number of influential nodes.

EVM-Compatible Blockchains

Some sidechains boast compatibility with the Ethereum Virtual Machine (EVM), enabling the execution of smart contracts coded in languages such as Solidity. This compatibility offers developers a familiar ecosystem. Essentially, EVM-compatible sidechains can seamlessly support decentralized applications (DApps) and execute Ethereum blockchain's smart contracts.

Exploring Sidechains: Advantages and Drawbacks


  • Scalability: Sidechains alleviate congestion on the main chain, enhancing overall performance.
  • Flexibility: Autonomy allows experimentation with various consensus mechanisms and parameters, fostering innovation.
  • EVM Compatibility: Seamless integration with existing Ethereum smart contracts simplifies development.


  • Decentralization Trade-offs: Higher throughput may compromise decentralization, concentrating power among validating nodes.
  • Security Concerns: Sidechains manage their security, potentially introducing additional risks.
  • Complexity: Setting up and maintaining sidechains demands significant resources, posing adoption challenges.

Sidechain Projects

  • Polygon: Utilizes sidechains to enhance Ethereum scalability through the Plasma framework, offering fast and cost-effective transactions for decentralized applications (DApps).
  • SKALE: Leverages elastic sidechains to provide developers with a high-performance and scalable platform for building decentralized applications, prioritizing developer accessibility.
  • Gnosis: Utilizes the xDai sidechain to enable quick and stable transactions, focusing on usability for applications requiring swift and economical transactions.
  • Loom Network: Specializes in creating scalable games and social applications on the blockchain, employing DPoS as its consensus mechanism to achieve high throughput.


In the dynamic realm of blockchain technology, sidechains offer a solution to the problem of scalability. They can function independently and have features such as EVM compatibility and bridges, which allow for a variety of applications and use cases. However, users and developers must be cautious and weigh the trade-offs, such as decentralization, security, and implementation complexity. As the blockchain space continues to develop, the importance of sidechains in creating a more scalable and adaptable ecosystem will likely increase further.

Follow us
Hexn operates under HEXN (CZ) s.r.o. and HEXN Markets LLC. HEXN (CZ) s.r.o. is incorporated in the Czech Republic with the company number 19300662, registered office at Cimburkova 916/8, Žižkov, Praha. HEXN (CZ) s.r.o. is registered as a virtual assets service provider (VASP). HEXN Markets LLC is incorporated in St. Vincent and Grenadines with the company number 2212 LLC 2022, registered office at Beachmont Business Centre, 379, Kingstown, Saint Vincent and the Grenadines