Listen to this episode:
In this episode of The Van Willum Sjorsnado, Aaron and Sjors discuss the Erebus attacks. The episode is a continuation of last week’s episode on Eclipse Attacks, a type of attack that isolates a Bitcoin node by occupying all of its connection slots to prevent the node from receiving transactions. Erebus attacks are Eclipse attacks in which an attacker essentially spoofs an entire part of the internet.
The Internet is made up of autonomous systems, essentially clusters of IP addresses owned by the same company as an ISP. Last week, the hosts explained how Bitcoin core nodes can counter Eclipse attacks by making sure they are connected to a variety of IP addresses from different autonomous systems. However, as it turns out, some autonomous systems can effectively act as bottlenecks when trying to reach other autonomous systems.
This allows an attacker who controls such a bottleneck to launch a successful Eclipse attack even against nodes that are connected to several autonomous systems.
Since its most recent release, Bitcoin Core has included an optional feature – ASMAP – to counter these types of Eclipse attacks. The hosts explain how mapping the internet has enabled Bitcoin Core contributors to create a tool that will ensure that Bitcoin nodes not only connect to various autonomous systems, but also ensure that they are not trapped behind these bottlenecks are.