# ParBlockchain: Leveraging Transaction Parallelism in Permissioned Blockchain Systems

## TL;DR

ParBlockchain introduces a new permissioned blockchain system that leverages transaction parallelism to improve performance in workloads with contention, addressing architectural limitations of prior systems.

## Contribution

The paper presents ParBlockchain, a novel permissioned blockchain designed within the OXII paradigm to support concurrent execution of conflicting transactions.

## Key findings

- ParBlockchain outperforms existing permissioned blockchains in contention-heavy workloads.
- Performance gains are consistent across various benchmark tests.
- Supports a range of contention levels effectively.

## Abstract

Many existing blockchains do not adequately address all the characteristics of distributed system applications and suffer from serious architectural limitations resulting in performance and confidentiality issues. While recent permissioned blockchain systems, have tried to overcome these limitations, their focus has mainly been on workloads with no-contention, i.e., no conflicting transactions. In this paper, we introduce OXII, a new paradigm for permissioned blockchains to support distributed applications that execute concurrently. OXII is designed for workloads with (different degrees of) contention. We then present ParBlockchain, a permissioned blockchain designed specifically in the OXII paradigm. The evaluation of ParBlockchain using a series of benchmarks reveals that its performance in workloads with any degree of contention is better than the state of the art permissioned blockchain systems.