Upstream Traffic Is Growing. What AT&T and Crown Castle Are Seeing

AT&T and Corning have announced a multiyear fiber agreement worth more than $3 billion as AT&T works toward its goal of expanding its fiber network to more than 60 million locations by the end of 2030. In a Fox Business interview, AT&T Chairman and CEO John Stankey pointed to a shift in network traffic that could have broader implications for communications infrastructure.

Stankey said upstream traffic is increasing at twice the rate of downstream traffic. He said the trend is one reason fiber’s symmetrical capacity is becoming increasingly important as data demand grows and AI applications develop.

“We’re seeing twice the increase occurring now in the upstream, going from the customer up into the network,” Stankey said.

The shift is also showing up in the mobile network. In a recent RBC Capital Markets interview, Crown Castle CFO Sunil Patel said mobile traffic has historically been roughly 80% download and 20% upload. With AI-driven applications increasing the amount of information being collected and sent into networks for processing and inference, he said that mix could eventually move closer to 60% download and 40% upload.

“We’re still at the beginning,” Patel said, describing AI as a potential demand driver for mobile data over the next several years.

More Data Moving Into the Network

Patel tied the change to what he called “physical AI,” where more information is gathered from the physical world and transmitted for processing. Stankey offered a similar example when discussing the potential growth of smart glasses and other wearables. Devices could capture video and send it to the cloud for analysis and inference, increasing the amount of data moving upstream.

For wireless infrastructure, Patel said the increase in traffic has physical implications as well. Moving more bits in and out of the network requires more energy, which can mean additional power requirements and larger antennas and other equipment to deliver greater throughput.

Despite the continued reduction in the size of radios and antennas, Patel said operators are occupying more space on towers today than they did five, 10 or 20 years ago, and he expects that trend to continue.

The impact may also vary by geography. Patel said larger urban and suburban areas, where mobile data traffic is concentrated, are likely to see the effects earlier and more significantly, although he sees opportunities across the network. He noted that mobile traffic is driven not only by people directly, but also by devices and infrastructure supporting them.

Fiber Remains Central

The AT&T-Corning agreement puts the changing traffic picture alongside a significant expansion of the company’s fiber footprint. Stankey said the agreement provides AT&T with stable pricing and supply as it works toward its more than 60 million-location goal.

For Corning, CEO Wendell Weeks said the agreement provides several years of committed demand, giving the company greater visibility as it expands capacity at its North Carolina optical-fiber manufacturing operation. The facility is already the company’s largest optical-fiber manufacturing plant, with about 5,000 employees.

Fiber also remains closely tied to Crown Castle’s mobile infrastructure. Patel said all of Crown Castle’s more than 40,000 towers are connected by fiber and have access to power. He said the company is also testing potential edge applications at tower sites, including sub-1 MW use cases involving inference and other computing needs.

As AT&T expands its fiber network and Crown Castle monitors changes in mobile traffic, both executives described the shift toward greater upstream traffic as being in its early stages, with AI expected to add to data demand in the years ahead.