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Comcast Reports 400 Gbps Internet Speeds in Hollowcore Fiber Test

Comcast
(Image credit: Comcast)

PHILADELPHIA—Comcast has announced what it believes is the first-ever end-to-end deployment of advanced “hollowcore” fiber optics in the world by an Internet provider.

Hollycore fiber is able to achieve much faster speeds and lower latency than traditional fiber optics because light travels nearly 50% faster through air than glass. That allows data to travel much faster through hollowcore fiber than through traditional fiber. The faster speed can be used to double the reach for latency critical applications and speed up the transaction rates by around 47%, Comcast reported. 

For the test, Comcast connected two locations in Philadelphia, which enabled network engineers to continue to test and observe the performance and physical compatibility of hollowcore fiber in a real-world deployment. 

This 40-kilometer hybrid deployment of hollowcore and traditional fiber is believed to be the longest in the world by an Internet provider. 

Comcast said it successfully tested bidirectional transmission (upstream and downstream traffic traveling on a single fiber), used coherent and direct-detect systems (allowing for forward and backward technology compatibility), and produced traffic rates ranging from 10 gigabits per second (Gbps) to 400 Gbps all simultaneously on a single strand of hollowcore fiber, the company said. 

“Hollowcore fiber is a leap forward in how we deliver ultra-fast, ultra-low latency and ultra-reliable services to customers,” said Elad Nafshi, executive vice president and chief network officer at Comcast Cable. “As we continue to develop and deploy technology to deliver 10G, multigigabit performance to tens of millions of homes, hollowcore fiber will help to ensure that the network powering those experiences is among the most advanced and highest performing in the world.”

For the test Comcast partnered with U.K. fiber provider Lumenisity. 

“We are proud to be working with Comcast on the next generation hollowcore fiber, which we believe unlocks exciting new potential for connectivity around the world,” said David Parker, executive chairman of Lumenisity.

Comcast noted that Hollowcore fiber will help to power the next generation of ultra-low latency technologies to support network virtualization, telemedicine, augmented and virtual reality, and other emerging services. 

Moving forward, Comcast is exploring opportunities to strategically deploy hollowcore fiber in select core- and access-network deployments. From 2017 to 2021, Comcast added more than 50,000 new route miles of fiber to its network and is actively building more fiber into cities and towns across the United States.

George Winslow is the senior content producer for TV Tech. He has written about the television, media and technology industries for nearly 30 years for such publications as Broadcasting & Cable, Multichannel News and TV Tech. Over the years, he has edited a number of magazines, including Multichannel News International and World Screen, and moderated panels at such major industry events as NAB and MIP TV. He has published two books and dozens of encyclopedia articles on such subjects as the media, New York City history and economics.