Here’s what caused yesterday’s O2 and SoftBank outages

It appears that most mobile carriers, including O2and SoftBank, have recovered from yesterday’s cell phone network outage that was triggered by a shutdown of Ericsson equipment running on their networks. That shutdown appears to have been triggered by expired software certificates on the equipment itself.
While Ericssonacknowledged in their press release yesterday that expired certificates were at the root of the problem, you may be wondering why this would cause a shutdown. It turns