Title:

Information Propagation in the Bitcoin Network

Abstract:
Bitcoin is a digital currency that unlike traditional currencies does not rely on a centralized authority. Instead Bitcoin relies on a network of volunteers that collectively implement a replicated ledger and verify transactions. In this paper we analyze how Bitcoin uses a multi-hop broadcast to propagate transactions and blocks through the network to update the ledger replicas. We then use the gathered information to verify the conjecture that the propagation delay in the network is the primary cause for blockchain forks. Blockchain forks should be avoided as they are symptomatic for inconsistencies among the replicas in the network. We then show what can be achieved by pushing the current protocol to its limit with unilateral changes to the client's behavior.

About the presenters:     

Samuel Welten received his M.Sc. degree in information technologies and electrical engineering from ETH Zurich, 
Switzerland. In 2010 he joined the Distributed Computing Group of Professor Roger Wattenhofer at ETH Zurich as a
Ph.D. student and research assistant. In 2013 he earned his Ph.D. degree for his work on new applications of internal
and external smartphone sensors. 

Christian Decker received his M.Sc. degree in computer science from
ETH Zurich, Switzerland in 2012. The same year he joined the
Distributed Computing Group of Professor Roger Wattenhofer at ETH
Zurich as a Ph.D. student and research assistant. He is currently
researching the networking aspects of Bitcoin and related digital
currencies.