CenturyLink‘s nationwide outage last month that affected 911 service for numerous consumers across the country could have been a lot worse, says the telco’s president and CEO.

Jeff Storey discussed the outage at this week’s 2019 Citi Global TMT West Conference in Las Vegas. The Federal Communications Commission (FCC) last week announced it is investigating the outage, but most of the agency’s operations have been shut down since Jan. 3.

The lengthy outage, which also affected some Verizon customers, occurred on Dec. 27. Restoration of services began that day and network traffic had normalized as of Dec. 29.

CenturyLink’s Jeff Storey

The fact that CenturyLink hasn’t integrated its network in the aftermath of acquisitions like Level 3 Communications lessened the impact of the outage, which affected voice, IP and transport services, Storey said.

“A lot of companies come in and integrate everything together, and make one platform … and we don’t do that,” he said. “We segment our network because our network is so large, so significant that we want to have it segmented because things happen. You get fiber cuts, you get equipment failures, and so our approach to integration actually facilitated it not being bigger than it was by making sure that we don’t just haphazardly integrate everything together. We operate a segmented network.”

Storey also said it affected “a relatively small percentage” of CenturyLink’s customer base, but it was a “significant outage and something that we did not like.”

“The source of the outage was a particular equipment vendor and a malfunction with one of those (network management) cards,” he said. “It created an inability for the system to continue to process capacity and it blocked our ability to control those nodes. And so we had to physically go out and shut things down, and restart them on that transport layer. Meanwhile, we’re moving circuits off to other capacities. It was an equipment failure that had a more dramatic impact than we would have wanted it to have.”

The equipment vendor is a U.S.-based company that has been part of CenturyLink’s network for a long time, Storey said.

“Several our companies have bought equipment from them, and historically they’ve been a great partner for us over a pretty long period of time,” he said.

In the meantime, Washington state Attorney General Bob Ferguson wants to hear from residents who were impacted.

“For the second time, CenturyLink has fallen short of its obligation to provide reliable 911 services for Washingtonians,” he said. “If you called for help during this outage, only to be met with a busy signal, please share your story with my office. We want to know exactly how CenturyLink’s failure impacted the people of our state.”

The state’s Utilities and Transportation Commission fined CenturyLink nearly $2.9 million for a six-hour 911 outage in 2014, Ferguson said.