Several internet service providers suffered an outage for longer than an hour on Monday due to a configuration error by Tier 1 network provider Level 3.
Service providers including Spectrum, Verizon, Cox, RCN, and Comcast’s Xfinity began experiencing disruptions across the U.S. at approximately 1 pm, and Level 3 said in a statement provided to Wired that the issue was resolved about 90 minutes later.
An Arbor Networks engineer told Wired that the disruption was caused by a misconfigured Autonomous System (AS), which issued incorrect IP address data, causing the Border Gateway Protocol (BGP) to spring a “route leak.”
“On Monday, Nov. 6, our network experienced a service disruption affecting some customers with IP-based services,” Level3 said in a statement. “The disruption was caused by a configuration error. We know how important these services are to our customers. Our technicians were able to restore service within approximately 90 minutes.”
Comcast apologized for what it called “an external network error” over Twitter. The outage recalls the massive outage caused by a DDoS attack on Tier 1 network provider Dyn last year.
CenturyLink agreed to acquire Level 3 for roughly $34 billion in cash and stock a year ago, and the deal recently closed, creating one of the largest networks in the world.
This article originally appeared on The WHIR.