Phys.org: “How could a small internet service provider (ISP) in Pennsylvania cause millions of websites worldwide to go offline? That’s what happened on June 24, 2019 when users across the world were left unable to access a large fraction of the web. The root cause was an outage suffered by Cloudflare, one of the internet’s leading content hosts on which the affected websites relied. Cloudflare traced the problem to a regional ISP in Pennsylvania that accidentally advertised to the rest of the internet that the best available routes to Cloudflare were through their small network. This caused a massive volume of global traffic to the ISP, which overwhelmed their limited capacity and so halted Cloudfare’s access to the rest of the internet. As Cloudflare remarked, it was the internet equivalent of routing an entire freeway through a neighbourhood street. This incident has highlighted the shocking vulnerability of the internet. In 2017 alone there were about 14,000 of these kinds of incidents. Given it is mission-critical for much of the world’s economic and social life, shouldn’t the net be designed to withstand not just minor hiccups but also major catastrophes, and to prevent small problems turning into much bigger ones? Governing bodies such as the EU Agency for Network and Information Security (ENISA) have long warned of the risk of such cascading incidents in causing systemic internet failure. Yet the internet remains worryingly fragile…”