206
23 March 2017 - 15h30
Bitcoin, its blockchain and the double spending problem : Bitcoin in a nutshell and safety analysis of recent improvement proposals
by Romaric Ludinard from ENSAI
Abstract:
Bitcoin allows monetary transfers among distant users without a trusted
third party. This is achieved by leveraging the famous blockchain, a
large scale distributed data structure aiming at recording the whole set
of transactions ever issued within the system. This structure is updated
by a special kind of entity, the miners, which validate and record
transactions in the blockchain. The update process mainly rely on a
probabilistic race among miners and it may lead to transient
inconsistencies called blockchain forks. A malicious user may leverage
these inconsistencies to spend a very same bitcoin multiple times to
different recipients. This misuse behavior is known as double spending
attack. Three improvement proposals have recently emerged to tackle
these issues by linearizing operations with byzantine tolerant consensus
algorithms. In this talk, I will present Bitcoin internal mechanisms ans
then I will focus on safety analysis of these three approaches.
