February 8, 2023

Archives for 2014

Consensus in Bitcoin: One system, many models

At a technical level, the Bitcoin protocol is a clever solution to the consensus problem in computer science. The idea of consensus is very general — a number of participants together execute a computation to come to agreement about the state of the world, or a subset of it that they’re interested in. Because of […]

On the Sony Pictures Security Breach

The recent security breach at Sony Pictures is one of the most embarrassing breaches ever, though not the most technically sophisticated. The incident raises lots of interesting questions about the current state of security and public policy.

How cookies can be used for global surveillance

Today we present an updated version of our paper [0] examining how the ubiquitous use of online tracking cookies can allow an adversary conducting network surveillance to target a user or surveil users en masse.  In the initial version of the study, summarized below, we examined the technical feasibility of the attack. Now we’ve made the […]

Why ASICs may be good for Bitcoin

Bitcoin mining is now almost exclusively performed by Bitcoin-specific ASICs (application-specific integrated circuits). These chips are made by a few startup manufacturers and cannot be used for anything else besides mining Bitcoin or closely related cryptocurrencies [1]. Because they are somewhere between a thousand and a million times more efficient at mining Bitcoin than a […]

Striking a balance between advertising and ad blocking

In the news, we have a consortium of French publishers, which somehow includes several major U.S. corporations (Google, Microsoft), attempting to sue AdBlock Plus developer Eyeo, a German firm with developers around the world. I have no idea of the legal basis for their case, but it’s all about the money. AdBlock Plus and the closely […]