2,931 research outputs found
Blockchain: A Graph Primer
Bitcoin and its underlying technology Blockchain have become popular in
recent years. Designed to facilitate a secure distributed platform without
central authorities, Blockchain is heralded as a paradigm that will be as
powerful as Big Data, Cloud Computing and Machine learning. Blockchain
incorporates novel ideas from various fields such as public key encryption and
distributed systems. As such, a reader often comes across resources that
explain the Blockchain technology from a certain perspective only, leaving the
reader with more questions than before. We will offer a holistic view on
Blockchain. Starting with a brief history, we will give the building blocks of
Blockchain, and explain their interactions. As graph mining has become a major
part its analysis, we will elaborate on graph theoretical aspects of the
Blockchain technology. We also devote a section to the future of Blockchain and
explain how extensions like Smart Contracts and De-centralized Autonomous
Organizations will function. Without assuming any reader expertise, our aim is
to provide a concise but complete description of the Blockchain technology.Comment: 16 pages, 8 figure
Efficient Concurrent Execution of Smart Contracts in Blockchains using Object-based Transactional Memory
This paper proposes an efficient framework to execute Smart Contract
Transactions (SCTs) concurrently based on object semantics, using optimistic
Single-Version Object-based Software Transactional Memory Systems (SVOSTMs) and
Multi-Version OSTMs (MVOSTMs). In our framework, a multi-threaded miner
constructs a Block Graph (BG), capturing the object-conflicts relations between
SCTs, and stores it in the block. Later, validators re-execute the same SCTs
concurrently and deterministically relying on this BG.
A malicious miner can modify the BG to harm the blockchain, e.g., to cause
double-spending. To identify malicious miners, we propose Smart Multi-threaded
Validator (SMV). Experimental analysis shows that the proposed multi-threaded
miner and validator achieve significant performance gains over state-of-the-art
SCT execution framework.Comment: 49 pages, 26 figures, 11 table
- …