Lumen beefs up long-haul network with 6M miles of fresh fiber

Undeterred by a residential fiber build that it moving slower than expected, Lumen Technologies is adding another heaping scoop of fiber to its plate. The company is looking to add 6 million miles of new fiber to its long-haul infrastructure by 2026.

To be clear, Lumen’s work will focus on its backbone network rather than its metro or residential assets. CTO Andrew Dugan told Fierce its newly announced target is part of a nationwide upgrade project Lumen has been chipping away at for the past five years or so. The idea, he said, is to use existing conduit laid by Level 3 Communications, Qwest, Broadwing and WilTel (which are all now part of Lumen) to replace old fiber with oodles of new ultra-low loss glass strands from Corning.

The operator is currently using Ciena’s 6500 optical platform for most of its network to deliver 400G services. Its infrastructure is currently scalable up to 800G. But Dugan explained the upgrade will give Lumen the flexibility to deploy new technologies such as OpenZR+ on dedicated lines.

“Having really low-loss fiber gives you technology flexibility that you wouldn’t have if you have older generations of fiber,” Dugan said. “If you look at the performance of OpenZR+ on the newer generations of fiber versus the older generations of fiber, it’s a material difference in terms of the amount of distance that you can go with those optics.”

Thus far, Dugan said Lumen has run around 6 million fiber miles across 24,000 route miles, implying an average fiber count of around 250. But the CTO noted its fiber counts range anywhere from a minimum of 216 to as high as 512, depending on the route. That compares to its legacy assets which used 96 count cables.

Lumen is looking to add at least another 6 million miles of fiber across its network, which would imply a much higher average fiber count closer to 500. But Dugan noted its hard to calculate exactly where it will land given its route miles are expected to increase as it undertakes new builds.

Dugan said the high fiber counts are a reflection of strong demand the company has seen for dark fiber. Though it sees interest across a “number of verticals,” he noted “webscalers are going to be a big consumer of dark fiber like this.” Dugan declined to comment on whether Lumen already has contracts in place, but added it is “very confident in the demand behind these builds.”

When its upgrade is done, Lumen expects to have 12 million miles of fresh fiber connecting more than 50 major metropolitan areas across the U.S. This will include infrastructure running down the coasts from Boston to Miami in the east and Seattle to San Diego in the west as well as transcontinental paths which somewhat mirror Interstates 80 and 10.

The network will span most of the lower 48 states, with Montana, North Dakota, South Dakota and West Virginia appearing to be the only states left out. Most of Wyoming will also be untouched, though Lumen does plan to connect the city of Cheyenne in the southern part of the state. Sources recently told Fierce that Lumen was looking to sell off its assets in Montana, North Dakota, South Dakota and Wyoming, though that offer has apparently been taken off the table for the time being. Dugan said the decision to skip these states was based on where the company can tap into existing conduit.

Permitting and trenching has proven to be a hurdle hindering Lumen's residential Quantum Fiber expansion. But Dugan noted the fact that Lumen is using existing conduit for its long-haul upgrade rather than digging means the work should be faster and easier by comparison. That’s a good thing, considering Dugan said the scope of the project will likely expand with time.

“The reality is the program grows every year because we continue to take orders for dark fiber from our customers,” he concluded. “The total program today is 12 million fiber miles. It’ll probably be bigger a year from now.”

Lumen isn't the only one investing in long haul fiber. Zayo Group has also been upgrading and expanding its IP network as has Windstream.


This story has been updated to clarify that Lumen provides 400G, not 400G and 500G, services.