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  • WhiteFiber’s 83 km, 136 Tbps Link Bets Fiber Can Pool AI Power Across Sites

    WhiteFiber’s 83 km, 136 Tbps Link Bets Fiber Can Pool AI Power Across Sites

    TL;DR · 30-second read

    The Short Version

    WhiteFiber, a company that rents out computing power for artificial intelligence, is now selling a way to make two data centers about 50 miles apart work as one giant computer. The two buildings are joined by a bundle of fiber-optic cables.

    Why it matters: the computers that train artificial intelligence are often limited by how much electricity a single building can get. WhiteFiber’s idea is to combine spare electricity at several existing buildings instead of building one enormous new site.

    The top speed is still being tested, and no customers have been named yet.

    StorageReview reported on September 25 that WhiteFiber (WYFI) has made WhiteFiber Continuum commercially available. Continuum is the productized version of Project Redwood, a two-site GPU supercluster the company first detailed in July. It links two HITRUST-certified QTS data centers 83 kilometers apart over 12 Zayo dark fiber strands, with DriveNets supplying the Ethernet network fabric and WEKA’s NeuralMesh supplying shared storage and memory.

    WhiteFiber rates the architecture at 136 Tbps of aggregate bandwidth, which it describes as 170 wavelength channels of 800 gigabits per second each, with 0.9 milliseconds of guaranteed round-trip latency. The July research result measured 111.2 Tbps on part of the fiber spectrum. Full-spectrum testing to confirm the guaranteed commercial specifications is underway, and the company has submitted patent applications for the implementation.

    Executive Summary

    WhiteFiber is selling a way to make GPUs in two separate buildings behave like a single cluster. GPUs are the chips that train and run AI models, and large training jobs have normally been confined to one building because the chips have to exchange data constantly. Continuum stretches that boundary to 83 kilometers by carrying the traffic over leased, unlit fiber that WhiteFiber lights itself, which the industry calls dark fiber.

    The launch matters because of what WhiteFiber says the design is for. The company pitches Continuum as a way to get past the power and space ceiling of a single campus. Enterprises would pool GPUs across sites, and telecom and metro facilities with spare power could contribute capacity to one logical cluster. If that works at the stated performance, the useful unit of AI capacity is no longer one building with enough electricity. It is any set of buildings connected by enough fiber.

    The headline number still needs confirmation. The 136 Tbps figure is a design rating that depends on additional wavelengths coming online and on full-spectrum testing now in progress. The figure WhiteFiber has actually measured is 111.2 Tbps, taken in July on part of the spectrum.

    Fiber as a Way Around the Single-Site Power Ceiling

    AI capacity is increasingly set by power: how many megawatts a single building or campus can draw. A megawatt is a million watts, and a large GPU campus uses many of them. A company that has filled its power allocation at one site usually faces a choice between waiting for more grid capacity and building a new campus from scratch. WhiteFiber offers a third option. Continuum lets enterprises pool GPUs across sites and add overflow training and inference capacity without a separate greenfield deployment. It also lets telecom and metro facilities with spare power and fiber join the same logical cluster.

    The design choice that makes this plausible is what crosses the link. According to WhiteFiber’s product page, both sites carry live traffic at the same time and only model gradients cross the 83 km connection. Gradients are the incremental updates each group of GPUs computes during training. The bulk of the work and data stays local to each site, and the two halves synchronize their learning over the fiber. A single job can span both sites, or the cluster can be split into independent workloads that burst from one site to the other as demand shifts.

    Fiber does not create power. It lets power that already exists in two places be used by one workload. The groups most affected are operators whose sites have stranded capacity, such as telco central offices and metro facilities with power to spare but too little of it to host a full cluster. Fiber owners like Zayo, whose dark fiber becomes part of the compute fabric, stand to gain as well. Enterprises that have maxed out a campus are the third group. Whether this changes where AI capacity gets built will depend on how much of a real training job’s performance survives the split, and WhiteFiber has not yet published that comparison.

    What 136 Tbps Establishes, and What It Does Not Yet

    The internal arithmetic holds together. 170 wavelength channels at 800 gigabits per second each come to 136 terabits per second. Dense wavelength-division multiplexing sends many separate colors of light down the same fiber strands, each carrying its own data stream. Adding wavelengths is how the design scales from the 111.2 Tbps measured in July to the 136 Tbps now rated.

    The status of the number matters to buyers. WhiteFiber says the design reaches 136 Tbps after additional wavelengths come online, and that full-spectrum testing is underway to confirm the guaranteed commercial specifications. Enterprises evaluating Continuum should treat 111.2 Tbps as the demonstrated figure and 136 Tbps as the contracted target until test results are released.

    The latency figure tells a different story. WhiteFiber guarantees 0.9 milliseconds round trip, which it says is within 8% of the physical limit for light in fiber over 83 km. There is little left to optimize, so distance itself is the fixed cost of the architecture. Longer links between sites add latency in proportion to distance. The 83 km result shows the approach works at metro-to-regional range, and it says nothing yet about sites much farther apart.

    Resilience and Data Boundaries as the Enterprise Pitch

    Continuum is also sold as a resilience and compliance product. WhiteFiber says neither site is a single point of failure, so training runs are designed to continue if one location goes down. For regulated industries, it says sensitive workloads can stay within their originating jurisdiction while failover and pooled compute happen across locations. HITRUST is a security and privacy certification framework widely used in healthcare, and the certification of both QTS facilities is aimed at that audience.

    CEO Sam Tabar framed the product around both themes, saying it is for enterprises that need AI compute to “hold up under compliance requirements, and not break when a single site has a problem.” These are credible goals for a two-site design. They are also claims about behavior under failure, and no failure test results have been released.

    A Partner Stack With a Patent Claim on Top

    Continuum is assembled from named partners. QTS provides the facilities, Zayo the fiber, DriveNets the Ethernet-based network fabric, and WEKA the shared storage and memory layer. WEKA CEO Liran Zvibel said NeuralMesh lets GPUs that sit many kilometers apart “operate as if the data were local.” DriveNets said its fabric is built to maximize GPU utilization across scale-across superclusters. Using Ethernet rather than proprietary interconnects for the inter-site fabric keeps the design within a widely supported networking standard.

    WhiteFiber calls Continuum the first commercially available distributed GPU supercluster architecture and has submitted patent applications for the implementation. Submitted applications are not granted patents. Because most of the stack comes from third-party vendors, WhiteFiber’s lasting advantage will likely come from its integration and operating know-how, and from customer contracts once it signs them.

    Background

    WhiteFiber, which trades under the ticker WYFI, provides AI infrastructure. In July it detailed Project Redwood, a research effort that connected GPUs in two data centers 83 km apart and measured 111.2 Tbps across the link. Its partners are well-established infrastructure suppliers. QTS operates data centers, Zayo owns and leases fiber networks, DriveNets builds Ethernet networking for AI clusters, and WEKA makes high-performance data storage software.

    Large AI models have traditionally been trained inside a single building. The GPUs doing the work exchange data constantly, and longer distances add delay. As single campuses run up against limits on how much power and space they can secure, operators have looked for ways to spread one workload across several sites. Continuum is WhiteFiber’s commercial answer to that problem.

    Sources

    Source: WhiteFiber Continuum Goes Commercial, Scaling Its 83 km Two-Site GPU Supercluster Design to 136 Tbps (StorageReview.com): WhiteFiber makes its two-site, 83 km GPU supercluster architecture commercially available with a rated 136 Tbps of inter-site bandwidth.

  • Nvidia’s 16 Zayo Routes Show New AI Fiber Gets Built Around an Anchor Tenant

    Nvidia’s 16 Zayo Routes Show New AI Fiber Gets Built Around an Anchor Tenant

    TL;DR · 30-second read

    The Short Version

    Nvidia, the company whose chips run most of today’s artificial intelligence, is the main customer for 16 new fiber-optic cable routes that Zayo is building across the United States.

    These cables are bundles of glass strands buried underground that carry data between cities. Zayo is laying them where there is enough electricity for the giant computer warehouses that AI needs.

    A rival network company says new long-distance cable usually loses money. Zayo’s answer was to sign a very large customer before digging. Neither company has said what it costs.

    Zayo Group has confirmed that Nvidia is the anchor tenant behind the “monster deal” it first described in April, when chief product and strategy officer Bill Long said the company was building 8,000 more route miles of fiber. Zayo executives told Fierce Network on August 7 that, in partnership with Nvidia, Zayo is building 16 new long-haul fiber routes in high-growth AI corridors across the U.S.: six entirely new (greenfield) routes and ten overbuilds that add fiber along existing Zayo paths. Nvidia is also leasing fiber on eight other Zayo long-haul routes that already had enough capacity.

    The program runs for several years, with the first routes expected as early as 2027 and the full set by 2030. Zayo declined to disclose the cost of the build or how much Nvidia is investing, saying only that it is “good business with an attractive return profile.”

    Executive Summary

    The world’s dominant AI chip supplier has become the named anchor customer for one of the largest new long-haul fiber builds in the United States. Long-haul fiber is the cable that links cities and regions, as opposed to the metro fiber inside a single city. Nvidia’s involvement spans 24 Zayo routes in total: six new, ten upgraded and eight leased as they stand.

    The announcement matters because it arrived the same week Lumen Technologies’ CFO, Chris Stansbury, said the economics of building new long-haul routes “stink” and that Lumen had walked away from several such deals. Lumen’s one exception, a Seattle-to-Minneapolis route called NorthLine, works financially because a partner is sharing it. Zayo’s Nvidia deal follows the same pattern. New intercity fiber for AI is getting built where a large, committed customer underwrites the route before construction begins.

    Zayo also says the routes were chosen by mapping where electrical power is available for future data centers, and that the conduit is sized well beyond Nvidia’s own needs. That makes the build relevant to every data center developer and cloud operator siting capacity along these corridors.

    Why an Anchor Tenant Changes the Math

    Building a new long-haul fiber route is expensive long before it earns anything. Zayo’s executives described what the work involves: dealing with hundreds of municipalities, regulators and permitting bodies, and coordinating multiple construction contractors. The money goes out during construction, while lease revenue arrives gradually over years. If a route is built on speculation and demand arrives slowly, the builder pays to finance an asset that is sitting idle.

    Lumen’s comments show this risk plainly. Stansbury said Lumen has “stepped away from a number of deals” because shareholder returns on greenfield routes are “awful.” Yet Lumen is building NorthLine because a partner, which it has not named, makes “the economics for that actually very good.” Zayo’s position rests on the same mechanism. With Nvidia committed as anchor tenant across 16 new or upgraded routes plus eight existing ones, Zayo starts construction with a large share of demand already contracted. It describes the result as an attractive return. The two companies reach opposite verdicts on greenfield fiber in general, but they agree on the condition that makes it work: a committed buyer before the trench is dug.

    This is a pattern in two data points, not a law of the market. Zayo also argues that its experience building new routes over the past seven or eight years gives it a cost and execution edge competitors lack. Because neither the cost nor Nvidia’s commitment has been disclosed, outsiders cannot check the return claim. What they can see is that the one greenfield build each company is pursuing has a large partner behind it.

    Fiber Is Now Following the Power Map

    Long said Zayo began seeing sharply higher long-haul demand about two years ago, in the form of orders for far higher fiber counts than before. The company responded by analysing where electrical power was available across the U.S. and concluding that those corridors were where bulk fiber would be needed. Bulk fiber means large quantities of strands sold to a few big users rather than small circuits sold to many.

    This reverses the traditional logic of long-haul networks, which were drawn between population centers and internet exchange points. AI data centers need hundreds of megawatts of electricity, and that power is scarcer than land or fiber, so it now decides where these facilities go. Fiber is being planned to meet them there. For developers, a site with both secured power and a new high-count fiber route nearby becomes more valuable. For utilities and regional economic planners, a new route can signal that data center projects are expected to follow.

    Built Bigger Than One Customer

    Zayo CEO Steve Smith said popular routes will carry at least 1,728 fibers, and that the conduit going into the ground can support up to 20,000. Conduit is the protective pipe that cables are pulled through, and it can be filled with more fiber over time. Long said Nvidia wanted a build package that would serve “the rest of the ecosystem” as well as its own use.

    For Zayo, oversizing the conduit turns an anchor-backed build into a multi-tenant asset. Pulling additional cable through existing conduit is typically far cheaper than new trenching, so every later customer on the route improves returns on the original construction. Cloud providers, newer GPU-cloud operators and other carriers would all be potential buyers. The main risk is timing. With completion stretching to 2030, the build depends on AI data center demand in these corridors holding up for years.

    Mostly Upgrades, Not Blank-Slate Builds

    Of the 24 routes Nvidia is using, only six are true greenfield builds. Ten are overbuilds on existing Zayo fiber, and eight needed no new construction at all. Overbuilds can typically draw on existing paths and permissions, which reduces permitting risk and cost compared with new routes. That mix suggests the deal leans heavily on Zayo’s existing footprint. It also suggests the greenfield portion, which Lumen called hardest to finance, is the smaller share of the program.

    Background

    Zayo Group is a U.S. fiber infrastructure provider that sells bandwidth and bulk fiber to carriers, cloud providers and large enterprises. Its executives say it has been the only company building new long-haul routes at scale in the U.S. over the past seven or eight years. It has also grown through acquisitions, including a $4.25 billion fiber deal with Crown Castle. Zayo reports that AI has driven a sharp rise in long-haul demand, with customers ordering much higher fiber counts than in the past.

    Nvidia is the leading supplier of the processors used to train and run AI models, and its customers are building large data centers wherever power is available. Lumen Technologies, formerly CenturyLink, operates one of the largest U.S. fiber networks and competes with Zayo for AI-driven long-haul demand.

    Sources

    Source: Zayo confirms Nvidia as its new ‘monster’ customer (Fierce Network): Zayo executives on the 16-route long-haul fiber build anchored by Nvidia, and Lumen’s view of greenfield route economics.

  • Zayo Closes $4.25B Crown Castle Fiber Deal, Redrawing the US Long-Haul Map

    Zayo Closes $4.25B Crown Castle Fiber Deal, Redrawing the US Long-Haul Map

    Zayo Group has completed its $4.25 billion acquisition of Crown Castle’s fiber business, according to a May 2, 2026 report from Fierce Network. The close finalizes a transaction first announced in March 2025, when Crown Castle agreed to exit fiber entirely by splitting the segment between Zayo, which took the fiber solutions business, and EQT, which took the small-cell operations, in a combined deal valued at roughly $8.5 billion.

    The completion makes Zayo — already one of North America’s largest independent bandwidth-infrastructure providers — a substantially bigger force in both long-haul and metro fiber, while returning Crown Castle to its roots as a pure-play wireless tower company.

    Executive Summary

    The announcement itself is short: the deal has closed. But the closing matters more than most, because it formally redraws the ownership map of US fiber at a moment when fiber has shifted from a commodity business to a strategic one. Long-haul fiber — the high-capacity routes that carry traffic between cities — and metro fiber — the dense local networks that connect buildings, data centers, and cell sites within a city — are both being repriced by the AI build-out, as hyperscalers and data center developers scramble to connect new campuses.

    For Zayo, the acquisition is a bet that scale wins in that environment: more routes, more conduit, more on-net buildings, and more ability to sell end-to-end connectivity to the customers spending most aggressively. For Crown Castle, it is the final step in unwinding a decade-long fiber strategy that the market never rewarded, refocusing the company on towers. Two companies looked at the same asset class and reached opposite conclusions — which is precisely what makes this deal worth watching.

    Fiber Is Having Its Moment — and Zayo Is Consolidating Into It

    For most of the 2010s, long-haul fiber was treated as a mature, low-growth business: capacity was abundant, prices declined steadily, and the assets traded hands repeatedly among private-equity owners. The AI infrastructure cycle has changed that calculus. New data center campuses are being sited in secondary and rural markets where power is available but fiber often is not, and connecting those sites — to each other and to major interconnection hubs — requires exactly the kind of route diversity and dark fiber (unused fiber strands leased whole, rather than as managed bandwidth) that Zayo sells.

    Absorbing Crown Castle’s fiber business gives Zayo a much denser metro footprint to pair with its national backbone. In connectivity, density compounds: the more buildings and data centers a provider can reach on its own network, the more of each customer’s traffic it can carry without paying another carrier, and the better its margins and win rates. That logic, not nostalgia for telecom assets, is what a $4.25 billion price tag implies.

    Two Readings of the Same Asset

    The striking feature of this transaction is the strategic divergence it crystallizes. Crown Castle spent heavily to build its fiber segment in the mid-2010s — including the reported $7.1 billion purchase of Lightower in 2017 — on the thesis that fiber and small cells would complement its tower business. Investors, including prominent activist shareholders, ultimately disagreed, arguing the fiber business consumed capital while earning returns below the tower segment’s. The March 2025 agreement to sell the entire segment, and now its completion, is the definitive verdict of that internal debate: Crown Castle is a tower company again.

    Zayo’s owners are making the opposite wager — that fiber’s return profile has structurally improved with AI-era demand, and that assets underperforming inside a tower REIT can perform well inside a focused fiber operator with a different cost base and sales motion. Both positions are defensible. Crown Castle’s shareholders wanted capital discipline and simplicity; Zayo’s private owners can hold a capital-intensive asset through a demand cycle without quarterly scrutiny. The deal is less a judgment on fiber than on who is best structured to own it.

    Integration Is Where $4.25 Billion Deals Are Won or Lost

    Zayo was itself assembled through dozens of acquisitions, so network integration is a core competency — but this is among the largest single integrations it has attempted. Merging two national fiber operations means reconciling network inventories, OSS/BSS systems (the operational and billing software that tracks what fiber exists and who is paying for it), overlapping routes, and two sales organizations, all without disrupting enterprise and carrier customers who treat connectivity outages as existential. Historically, fiber roll-ups have stumbled less on the assets than on the systems and service quality during the merge.

    There is also a balance-sheet dimension. Fiber consolidation of this scale is typically debt-financed, and the sector’s private owners have been navigating a higher-rate environment than the one in which many of these assets were last underwritten. Strong AI-driven demand improves the revenue side of that equation, but execution risk during integration is the variable Zayo most controls.

    What Changes for the Market

    For enterprise and wholesale buyers, one fewer independent fiber provider means the competitive set in some metros narrows, which bears watching on pricing and on route diversity — customers who deliberately bought from both companies for redundancy may now find both circuits on one network. For data center developers, a larger Zayo is arguably good news: a single counterparty that can deliver metro entrances and long-haul routes together simplifies procurement for new campuses. And for the remaining independent fiber operators, the deal resets the benchmark for what scaled fiber platforms are worth, which tends to invite further consolidation rather than end it.

    Background

    Zayo was founded in 2007 and grew into one of North America’s largest independent fiber operators through a long series of acquisitions, going public in 2014 before being taken private in 2020 by a consortium led by DigitalBridge and EQT. Crown Castle, one of the largest US tower REITs, moved aggressively into fiber in the mid-2010s — including the reported $7.1 billion acquisition of Lightower in 2017 — betting that fiber and small cells would complement its tower franchise.

    That bet faced years of investor pushback over returns on the fiber capital, culminating in a strategic review and the March 2025 agreement to sell the entire fiber segment for roughly $8.5 billion, split between Zayo and EQT. The May 2026 closing of Zayo’s $4.25 billion portion completes Crown Castle’s retreat to towers and lands just as AI data center construction has made fiber routes one of the most sought-after asset classes in digital infrastructure.

    Source: Zayo closes $4.25B Crown Castle fiber deal — Fierce Network’s May 2, 2026 report on the completion of Zayo’s acquisition of Crown Castle’s fiber business.