The bandwidth wars just heated up.

Comcast has announced trials are underway for a new multigigabit Internet service that is already showing upstream and downstream throughputs of more than 4 gigabits per second. That’s twice as fast as the company’s current top home options and four times faster than high-end options from Comcast, Google, and Verizon.

The technology, based on Broadcom’s full-duplex DOCSIS 4.0 computer chip, uses the same type of connections that are already installed in hundreds of millions of homes around the country, Comcast said. The advancement enables service providers to use network spectrum more efficiently, which results in the exponentially higher speeds.

In other words, the technology likely won’t require rewiring one’s house or the cable network on one’s street, potentially meaning a faster rollout upon release.

“The trial is an important step forward on the path to 10G“—an ambitious goal to reach 10Gbps—”a global industry initiative to develop and deploy new network technology to dramatically increase upload and download capacity,” Comcast said in a statement.

What could you do with a 4Gbps connection? You could conceivably download a full movie in as little as a few seconds. (Qualcomm’s 4G modem tops out at 1.2Gbps and can download a high-definition movie file in 30 seconds.)

The technology could also give pro gamers, including Fortnite fanatics, an advantage over foes. The superfast service would mean basically no lag in online matches.

Lightning-fast Internet speeds come with risks, though. Avid users could blow past their data caps quickly. And viruses and malware that prey on vulnerable people will be able to more quickly slip onto a system, without the opportunity to cancel a download before it is complete.

The service is still in early testing. Comcast gave no time frame for the rollout of a possible product.

“We are always pushing the envelope to stay ahead of our customers’ growing needs,” said Charlie Herrin, chief product officer at Comcast Cable. “This milestone is particularly exciting, because this technology is an important step forward toward unlocking multigigabit upload and download speeds for hundreds of millions of people worldwide, not just a select few.”

Comcast conducted the trials in Philadelphia, its hometown, and Denver.

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