From T1s to 400G: OneNet’s Network Evolution Journey

As OneNet celebrates our 30th anniversary, we are sharing a behind-the-scenes look at how our network evolved from T1 to 400G, continuously meeting the growing demands of our partners and subscribers.

When OneNet officially began operating in 1996, the network looked nothing like today’s multi-hundred‑gigabit backbone. Built to connect Oklahoma’s education, research, healthcare, and public-serving institutions, it was a network where every megabit mattered.

Early connections were modest by today’s standards: many sites relied on T1 service, sometimes at 56 Kbps, while larger locations used bonded T1s or DS3s.

“We provided most subscribers with DS3s (Mbps), but they were often dedicated to full-motion video devices that carried classes,” Brian Burkhart, chief technology officer, said. “Most colleges that served as OneNet points of presence were connected with four T1s bonded together to provide 6Mbps of internet traffic. Most K-12 schools and libraries were connected with either a channelized T1 at 56Kbps or a full 1.544Mbps T1.”

Building a Statewide Network

The leap from dial‑up to dedicated connectivity was transformative. Persistent connections made email and basic web browsing available across institutions, just as schools began building their

first web presence. It also changed expectations; going online stopped being an event and became the default. To help organizations get started, OneNet provided web and email hosting servers. As the realm of networks and connectivity evolved, OneNet underwent its own development by adopting H.323 video conferencing over IP, making it one of the earliest adopters and enabling it to assist subscribers with integration and functionality testing as video over IP began to gain traction. H.323 revolutionized distance learning for the state.

“The standards were still new, so not all H.323 devices were able to communicate without specific settings. Switching from full-motion video to IP-based video opened up that reserved bandwidth for general use,” Burkhart said.

OneNet’s Turning Point

A key turning point came in 2002, when a major upgrade introduced SONET transport that could carry Ethernet. That shift enabled higher‑bandwidth delivery to larger campuses and helped OneNet make Ethernet a native service across the backbone. In 2006, OneNet expanded its capacity again to deliver higher bandwidths with an additional $8.1 million investment in routing, switching, and optical equipment, enhancing service across the backbone and improving routing capabilities.

In 2011, OneNet undertook a $7.8 million network upgrade that incorporated multi-protocol label switching (MPLS). This technology enables multiple services to operate over the same network,enhancing efficiency and flexibility.

“One of MPLS’s key benefits is the ability to use network-based virtual private networks, which allow layer 2 and layer 3 services to function as if they are occurring on a single device. Additionally, MPLS increases the network’s resilience through fast rerouting in case of device or path failures,” Burkhart said.

The 100G Era: Internet2, OCAN, and the Statewide Ring

Another major milestone came in 2012, when OneNet became the first network in the nation to connect to Internet2 at 100Gbps, giving OneNet’s connectivity an edge in additional capacity on the nation’s largest research backbone. Internet2 provides an uninterrupted network connection to institutions primarily focused on research and education; however, this enhanced Internet2 connectivity benefited all OneNet subscribers.

In 2013, the completion of the Oklahoma Community Anchor Network (OCAN) improved OneNet’s connectivity to Oklahoma’s rural communities through a 1,100-mile fiber network. OCAN connects 35 Oklahoma counties and 93 community anchor institutions, which include schools, libraries, healthcare facilities, and public safety organizations.

OCAN serves rural areas by providing high-speed broadband access and fostering public-private partnerships. These partnerships not only connect community anchor institutions but also enable local private telecommunications providers to expand connectivity to private businesses, supporting economic growth and improving access to essential services across the state.

In 2015, OneNet deployed a statewide 100Gbps ring to support Oklahoma’s research universities. Demand was rising on multiple fronts: data‑intensive research, richer instructional content, and teaching and learning moving largely online. One‑to‑one device initiatives and mainstream streaming platforms also reset what “normal” networking looked like. The 100Gbps ring increased bandwidth availability for Oklahoma’s research universities and provided faster connections to Internet2.

Widespread Research Connections

As usage grew, content providers, like Netflix, Facebook, and Google, began placing servers directly in OneNet’s infrastructure to improve performance and reduce reliance on off‑network internet transit.

“OneNet has direct network peering with many content providers. Internet2 runs a service called the Internet2 peering exchange, where many content providers and other networks peer to

improve connectivity to their services,” Burkhart said.

National and regional research networks have also been central to OneNet’s capacity growth. OneNet partners with Internet2, Great Plains Network, Midsouth U.S. Internet Exchange (MUS-IX), and other state research and education networks to deliver connectivity across the region and the rest of the world.

“OneNet collaborates with neighboring states in the region through the Great Plains Network. Multiple Internet2 connections enter the GPN network in Tulsa, Kansas City, and Dallas. By facilitating peering among state networks and offering various services, we strengthen collaboration among the states,” Burkhart said.

The 400G Era

By 2025, the state’s research institutions began requiring even higher-bandwidth connectivity. To meet these rapidly increasing bandwidth requirements, OneNet deployed a 400Gbps network backbone upgrade.

Early in the project, connections to Internet2 and Great Plains Network were upgraded to 400Gbps, and major research universities, including the University of Oklahoma and Oklahoma State University, were connected at 400Gbps. This upgrade supported large-scale research computing and data transfer needs.

During this time, OneNet upgraded 48 hub sites with new equipment. These included upgraded connectivity to Dallas sites.

This upgrade significantly increased capacity at each hub site, enabling OneNet to deliver up to 100Gbps of service to subscribers statewide. The upgrade also streamlined infrastructure by reducing the number of router models in use, improving efficiency while enabling more cost-effective service delivery.

400G Today, 800G Tomorrow

Faster optics are already within reach. The new OneNet routers deployed as part of the 400Gbps upgrade are capable of handling 800Gbps to meet subscribers’ future bandwidth needs, preparing OneNet for future growth.

“As 1.6 Tbps technology becomes viable, OneNet is positioned to scale once again, continuing its long-standing pattern of staying ahead of demand,” Burkhart said.

Moving Forward

From T1 to 400Gbps, OneNet’s evolution reflects decades of innovation and adaptation. Each upgrade has expanded opportunities for universities, researchers, and communities across Oklahoma.

OneNet’s commitment to connectivity and capacity continues to make it a vital resource and partner in Oklahoma’s future.