For what it’s worth, I used to be a “fiber guy,” but my jobs pushed me in a different direction. So, I was amazed to read (courtesy of the repost by Doug Mohney) this LinkedIn post by Tom Spackman CEO of Gigabit Fiber.
Here is the posting from Tom:
From T1 to 400G
On Friday, we turned up our first 32 × 400G optical wave system for a hyperscaler. From P.O. to live traffic, the project took less than 30 days. It certainly helps that Gigabit Fiber has next generation fiber infrastructure strategically prepositioned, but this feat would have been unimaginable during the era of T-carrier circuits provided by the incumbent monopolies (think AT&T and Verizon), when provisioning a T-1 could take months or even years. Today, hyperscale customers expect terabit-scale connectivity on demand, and modern optical transport makes it possible.
In the 1970s a T-1 (DS1) could carry 24 voice channels or 1.544 Mb/s of data. Yes, I was alive in the 1970’s, but when I started in telecom in the late 1990’s, T-1s were still the standard wholesale circuit. Fast forward to today: a 400G wavelength moves 400 Gb/s, roughly 260?000× the throughput of a T-1. Aggregate 32 of these massive pipes and you get 12.8 Tb/s — that’s more than 8 million times a T-1.
Why is 400G the new baseline?
Economics & efficiency: 400G ports follow the IEEE standard and deliver four times the throughput of 100G while using fewer ports and less power. One 400G interface costs less and draws less energy than four 100G interfaces.
Demand is exploding: Zayo’s 2025 Bandwidth Report shows customers adopting 400G for its efficiency, space savings and future-proofing. By 2024, 400G capacity purchases accounted for the largest share of total terabits purchased, and software/tech companies sourced 82.15 % of their wavelength capacity in 400G increments.
Fiber boom: In the same report, Zayo notes a 600% increase in metro dark-fiber purchases from 2020–2024, including a 268% year-over-year spike in 2024. Hyperscalers account for more than half of Zayo’s metro dark-fiber purchases, as they want control over massive bandwidth pipes as their critical functions are built upon this foundational infrastructure.
As AI, machine learning and cloud workloads surge, 400G has become the new baseline. It offers enough headroom for modern applications and scales easily to terabit levels by combining wavelengths and today 400G waves are the new T-1 – the standard building block for next-generation networks.
What this means for our industry
The era after the breakup of AT&T crowned the T-1 circuit as the gold standard. Over thirty years later, I am still in the industry and the 400G has taken that mantle. The technology, economics and demand all points to the same conclusion: 400G waves are the new T-1, and the providers who can deploy them quickly will lead the next phase of the bandwidth boom.
Now to be fair to my former regulated life, the goal was never to restrict companies in meeting their bandwidth requirements, but it always had to do with shared costs. Telephone networks have traditionally been built on sharing resources. A T-1, once the backbone of the phone network, divided into 24 voice channels using Time Division Multiplexing (TDM). The carrier could share the cost and keep the customer prices low. So, when the carrier was asked to provide a 10 Mb circuit the answer provided fit the network (sell 7 T-1s), but not the need (adding a costly mux on both ends as a customer expense.) Then came the years of SONET, where the carrier could share (in theory) four 10 Mb circuits on a T-3 over fiber.
Enough history… let’s get to the point. At 400G, the edge now has a great transport to the cloud and keeping things aggregate at the customer gets the benefit of the shared economics the carriers once relied upon to keep costs down. It also means edge compute is the point where cloud vs. edge and device processing is decided.
One last thing to point out is that Gigabit Fiber is a “dark fiber” operator, meaning customers get direct cost of the number of strands of fiber they use. Because of the ribbons of glass that were sold to the big guys, followed by the Fiber Bragg Grating pushing colors in the existing lit up glass, making the rest of strand available for sale to other providers (just in case right of ways were a problem). Often “pigtails” were all that was needed to transfer the signal (light) from one strand to another.
Where am I going with all this? When I was working on fiber, we borrowed from “Field of Dreams” with the phrase “if you build it they will come.” Tom’s article points to the fact that customers have already built it internally; they just need someone to match their needs and that will not be from the big companies, but from the companies that meet their demand.
Edge compute is the likely battlefield for this nascent market. Based on what I hear from enterprises, companies like Gigabit Fiber have the odds in their favor, currently. We still need to see what comes from all these edge deals between the hyperscalers and the major carriers before we declare victory. However, for enterprise internal requirements for edge compute, dark fiber clearly has the advantage.
Edited by
Erik Linask
