Cryptology ePrint Archive: Report 2017/1070

The Transaction Graph for Modeling Blockchain Semantics

Christian Cachin and Angelo De Caro and Pedro Moreno-Sanchez and Björn Tackmann and Marko Vukolić

Abstract: The advent of Bitcoin paved the way for a plethora of blockchain systems supporting diverse applications beyond cryptocurrencies. Although in-depth studies of the protocols, security, and privacy of blockchains are available, there is no formal model of the transaction semantics that a blockchain is supposed to guarantee.

In this work, we fill this gap, motivated by the observation that the semantics of transactions in blockchain systems can be captured by a directed acyclic graph. Such a transaction graph, or TDAG, generally consists of the states and the transactions as transitions between the states, together with conditions for the consistency and validity of transactions. We instantiate the TDAG model for three prominent blockchain systems: Bitcoin, Ethereum, and Hyperledger Fabric. We specify the states and transactions as well as the validity conditions of the TDAG for each one. This demonstrates the applicability of the model and formalizes the transaction-level semantics that these systems aim for.

Category / Keywords: applications / Blockchain, Ethereum, Distributed ledgers

Date: received 3 Nov 2017

Contact author: cca at zurich ibm com

Available format(s): PDF | BibTeX Citation

Version: 20171110:151455 (All versions of this report)

Short URL:

Discussion forum: Show discussion | Start new discussion

[ Cryptology ePrint archive ]