As blockchain technology continues to gain traction and adoption, the issue of scalability has become one of the most pressing concerns. Theoretically, a blockchain could handle an infinite number of transactions, but in practice, this isn’t the case. The more transactions that are executed on a blockchain, the slower and more expensive the process becomes. This has led to the development of various scaling techniques, including layer 2 solutions, which aim to alleviate the scalability problem.

Layer 2 scaling solutions are designed to help blockchains achieve higher transaction throughput by moving some of the processing off-chain. This allows more transactions to be processed in parallel, increasing the overall throughput of the network. Several layer 2 scaling techniques have been developed, each with its strengths and weaknesses. In this article, we will provide an overview of the most popular layer 2 scaling solutions.

Lightning Network

The Lightning Network is a layer 2 scaling technique for the Bitcoin blockchain that was developed in 2015. It allows users to conduct micro-transactions quickly and cheaply off-chain, and then settle the balance on the main blockchain later. This drastically reduces the number of transactions that need to be executed on the main blockchain, which increases its processing capacity. The Lightning Network has been successful in reducing transaction fees and processing times for Bitcoin.


Plasma is a layer 2 scaling technique that was developed by Vitalik Buterin and Joseph Poon for the Ethereum blockchain. The idea behind Plasma is to create a series of interconnected blockchains, with each blockchain processing a subset of Ethereum’s transactions. This allows for more transactions to be processed in parallel and reduces the overall load on the main Ethereum blockchain. Plasma is a promising layer 2 scaling solution for Ethereum and has been a subject of ongoing research.


zkRollup is a type of layer 2 scaling solution that uses zero-knowledge proofs to compress multiple transactions into a single transaction. This technique allows for a significant increase in the number of transactions that can be processed per second while still maintaining the decentralization and security benefits of blockchain technology. zkRollup has the potential to be applied to various blockchains and has generated a lot of interest within the blockchain community.

Optimistic Rollups

Optimistic rollups are similar to zkRollups in that they also compress multiple transactions into a single transaction. However, they do not use zero-knowledge proofs; instead, they employ a form of optimistic computation. In optimistic rollups, all transactions are initially processed off-chain, and only the transaction summaries are submitted to the main blockchain for verification. This allows for a significant increase in the number of transactions that can be processed while still maintaining the integrity and security of the blockchain.


The scalability issue is one of the most challenging problems facing blockchain technology. Layer 2 scaling solutions offer a promising solution to increase transaction throughput in a secure and decentralized manner. From Lightning Network to Rollups, various layer 2 scaling solutions have been developed and are being actively researched. These solutions provide a glimpse into the future of blockchain technology and pave the way for more efficient and secure blockchain-based applications.