Criticality Aware Orderer for Heterogeneous Transactions in Blockchain

Abstract

Blockchain enabled systems are becoming increasingly popular in recent times, spreading across variety of domains such as finance, supply chain management, healthcare, etc. These systems usually involve homogeneous transactions with similar latency requirements. However, as increasingly complex systems are enabled through blockchain, they will include a variety of heterogeneous transactions having different latency requirements. For example, an IoT system such as smart building may include transactions corresponding to varied services like payment, biometric registration, etc. Present blockchain systems are transaction metadata agnostic in their ordering step i.e. during ordering and bundling of transactions into blocks. Since transactions in complex systems are heterogeneous in nature, a framework that prioritizes transactions having low latency requirements would be more suitable. In this work, we propose various transaction criticality aware ordering services and comprehensively evaluate them on a handcrafted smart building scenario. Our experiments demonstrate that a single ordering service is not suitable (in terms of number of transactions missing their latency requirement) for all practical scenarios. We demonstrate that selection of a suitable ordering service may give up to 58.25% improvement over other ordering services.