.Bitcoin is a disruptive new cryptocurrency based on a decentralised open-source protocol which has been gradually gaining momentum. Perhaps the most important question that will affect its success, is whether or not it will be able to scale to support the high volume of Bitcoin transactions required from a global currency system.

The authors investigate the implications of having a higher transaction throughput on Bitcoin’s security against double-spend attacks. We show that at high throughput, substantially weaker attackers are able to reverse payments they have made, even well after they were considered accepted by recipients.

They address this security concern through the GHOST rule, a modification to the way Bitcoin nodes construct and re-organise the blockchain, Bitcoin’s core distributed data-structure. GHOST has been adopted and a variant of it has been implemented as part of the Ethereum project, a second generation distributed applications platform.

This paper has focused primarily on the effect network delays have on Bitcoin’s security from double-spend attacks. In this context the authors presented GHOST and a suggestion for the modification of the protocol. This suggestion should secure a higher rate of Bitcoin transactions at the processing stage. Want to find out more about how Bitcoin transactions can be accelerated throughout the network? Read this research!