Comcast, the nation's largest broadband provider and one of the largest pay-TV providers, had a nationwide outage of some services Friday.
The Philadelphia-based company said it was aware Friday afternoon some of its TV, broadband and telephone customers across the U.S. were affected.
The apparent cause? A pair of cuts in vital fiber at its network partners.
“We identified two, separate and unrelated fiber cuts to our network backbone providers," Comcast said in a statement provided to USA TODAY just before 5 p.m. ET. "Our engineers worked to address the issue immediately and services are now being restored to business and residential internet, video and voice customers. We again apologize to anyone who was impacted.”
Initially, Comcast had said a single "fiber cut" had been affecting its customers, as well as other providers.
Customers in Philadelpha, Baltimore and elsewhere on the east coast reported outages of internet and video service on Twitter and on Internet monitoring site Downdetector.com, where outage reports began arriving just after 12:30 p.m. ET.
Other reports of outages from Comcast customers were from Seattle, San Francisco and Atlanta, according to Downdetector.com. CNBC, a network within Comcast-owned NBC Universal, first reported the outage.
Comcast is one of the nation's largest pay-TV providers with more than 22 million subscribers, and the largest broadband provider with more than 26 million subscribers, according to Leichtman Research Group. The company also provides broadband and video to more than 2 million businesses.
San Francisco-based Network monitoring and intelligence firm ThousandEyes began seeing network issues across the Net beginning about 12:15 p.m. ET. By about 4:30 p.m. ET, network issues were appearing to be resolved, the firm said.
Many internet users beyond Comcast's own 25 million subscriber base were affected, too, according to ThousandEyes. That's because other traffic travels across the provider's network, because it serves as part of the backbone connecting various regions of the nation. "This is a really good illustration of how interconnected a lot of these networks are," said Angelique Medina, senior product marketing manager at ThousandEyes.
"It is kind of like a domino effect. Any one provider can potentially have a big impact on a number of users," she said. "In this case, because it was Comcast, the blast radius was just massive."
