Blockchain Scaling Using Rollups: A Comprehensive Survey

Abstract

Blockchain systems have seen much growth in recent years due to the immense potential attributed to the technology behind these systems. However, this popularity has outlined a critical scalability issue that most blockchain systems are now confronted with. With their increasing popularity comes an increasing amount of load on the system. Several scaling solutions that modify either the functioning of the underlying protocol or that build on top of them have already been proposed; however, each of these solutions comes with their advantages and disadvantages. This paper aims to survey the current state-ofthe-art of rollups as a scaling solution. We discuss the mode of operation of the different types of rollups, outline state-of-the-art implementations of each type together with their features and limitations. We also conduct a performance analysis comparing these implementations. Finally, we outline avenues for future research around rollups as a scaling solution.

Instant Function Calls Using Synchronized Cross-Blockchain Smart Contracts

“…Multiple approaches exist. For instance, optimistic rollups allow the offchain execution of transactions, while observers can challenge the results if misconduct is detected [66]. Another concept that recently gained traction is using zero-knowledge proofs to guarantee correct off-chain transaction execution [66].…”

“…For instance, optimistic rollups allow the offchain execution of transactions, while observers can challenge the results if misconduct is detected [66]. Another concept that recently gained traction is using zero-knowledge proofs to guarantee correct off-chain transaction execution [66]. Since transactions do not have to be executed by all network participants but only a small set, layer-2 concepts generally scale well and incur less execution costs.…”

Blockchain and Holochain in Medical Education from Planetary Health and Climate Change Perspectives

“…non-compliance with General Data Protection Rule of European Union), immutability issues (records are immutable on blockchain network), and scalability issues (slow and expensive) (27). Despite efforts to solve the scalability problem using solutions such as rollups (28), the data-centric approach of blockchain continues to pose challenges that hinder its widespread adoption. While decentralization is a crucial aspect, blockchain's data centric paradigm may not be the most effective solution to achieve it, as Walsh stated "there are reasons to be sceptical about blockchain and its application to healthcare professional education" (29).…”

ALDER: Unlocking blockchain performance by multiplexing consensus protocols

“…BitcoinNG lets each leader appends multiple blocks before another leader is found and takes over with proposing new blocks. Layer-2 solutions, such as rollups [27], have been proposed to address performance improvement without handling the complexity of consensus protocols. Despite all these techniques suffering from the same performance bottleneck due to the store-validate-forward block dissemination mechanism, they are solutions that can be applied to a specific blockchain protocol only.…”