Proceedings ArticleDOI
A Secure Sharding Protocol For Open Blockchains
Loi Luu,Viswesh Narayanan,Chaodong Zheng,Kunal Baweja,Seth Gilbert,Prateek Saxena +5 more
- pp 17-30
TLDR
ELASTICO is the first candidate for a secure sharding protocol with presence of byzantine adversaries, and scalability experiments on Amazon EC2 with up to $1, 600$ nodes confirm ELASTICO's theoretical scaling properties.Abstract:
Cryptocurrencies, such as Bitcoin and 250 similar alt-coins, embody at their core a blockchain protocol --- a mechanism for a distributed network of computational nodes to periodically agree on a set of new transactions. Designing a secure blockchain protocol relies on an open challenge in security, that of designing a highly-scalable agreement protocol open to manipulation by byzantine or arbitrarily malicious nodes. Bitcoin's blockchain agreement protocol exhibits security, but does not scale: it processes 3--7 transactions per second at present, irrespective of the available computation capacity at hand. In this paper, we propose a new distributed agreement protocol for permission-less blockchains called ELASTICO. ELASTICO scales transaction rates almost linearly with available computation for mining: the more the computation power in the network, the higher the number of transaction blocks selected per unit time. ELASTICO is efficient in its network messages and tolerates byzantine adversaries of up to one-fourth of the total computational power. Technically, ELASTICO uniformly partitions or parallelizes the mining network (securely) into smaller committees, each of which processes a disjoint set of transactions (or "shards"). While sharding is common in non-byzantine settings, ELASTICO is the first candidate for a secure sharding protocol with presence of byzantine adversaries. Our scalability experiments on Amazon EC2 with up to $1, 600$ nodes confirm ELASTICO's theoretical scaling properties.read more
Citations
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Journal ArticleDOI
Scaling Blockchain via Layered Sharding
TL;DR: PYRAMID as discussed by the authors is a layered sharding system that allows the nodes with better hardware to participate in multiple shards and store the blockchains of these shards thus they can validate and execute the cross-shard transactions without splitting.
Book ChapterDOI
Committee selection in DAG distributed ledgers and applications.
TL;DR: In this paper, the authors propose several solutions to the committee selection problem among participants of a DAG distributed ledger based on a ledger intrinsic reputation model that serves as a selection criterion, but the main difficulty arises from the fact that the DAG ledger is a priori not totally ordered and that the participants need to reach a consensus on participants reputation.
Posted Content
How to Securely Prune Bitcoin's Blockchain
TL;DR: CoinPrune as discussed by the authors is a snapshot-based pruning scheme that is fully compatible with Bitcoin and can be deployed through an opt-in velvet fork, i.e., without impeding the established Bitcoin network.
Posted Content
Read-Uncommitted Transactions for Smart Contract Performance
TL;DR: This paper perceives the blockchain as a transactional data structure, using this analogy in the development of a new algorithm, Hash-Mark-Set (HMS), that improves transaction throughput by providing a Read-Uncommitted view of state variables.
Book ChapterDOI
VAPOR : A Value-Centric Blockchain that is Scale-out, Decentralized, and Flexible by Design
Zhijie Ren,Zekeriya Erkin +1 more
TL;DR: In this article, value-centric blockchains (VCBs) are proposed, in which the states are specified as values (or more comprehensively, coins) with owners and the state transition records are then specified as proofs of the ownerships of individual values.
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