AUTHOR=Bistarelli Stefano , Mercanti Ivan , Santini Francesco 

TITLE=An Analysis of Non-standard Transactions

JOURNAL=Frontiers in Blockchain

VOLUME=2

YEAR=2019

URL=https://www.frontiersin.org/journals/blockchain/articles/10.3389/fbloc.2019.00007

DOI=10.3389/fbloc.2019.00007

ISSN=2624-7852

ABSTRACT=<p>In Bitcoin, the most common kind of transactions is in the form “Bob pays Alice,” and it is based on the <italic>Pay to-Public Key Hash</italic> (<italic>P2PKH</italic>) script, which are resolved by sending the public key and a digital signature created by the corresponding private key. P2PKH transactions are just one among many <italic>standard</italic> classes: a transaction is standard if it passes <italic>Bitcoin Core IsStandard()</italic> and <italic>IsStandardTx()</italic> tests. However, the creation of <italic>ad-hoc</italic> scripts to lock (and unlock) transactions allows for also generating <italic>non-standard</italic> transactions, which can be nevertheless broadcast and mined as well. In this work, we explore the Bitcoin block-chain with the purpose to analyze and classify standard and non-standard transactions, understanding how much the standard behavior is respected.</p>