USB4 enables hubs with multiple USB-C ports


A Thunderbolt 3 cable is also a USB4 cable.
If the specs for USB4 are familiar, that’s because they’re built on the Thunderbolt 3 standard already in most Macs.
Photo: Caldigit

Today’s USB-C hubs include multiple USB-A ports, but can’t add additional USB-C ports. This will change when USB4 gets widely implemented, which just took a big step forward with the specifications for this standard being finalized.

And users should welcome an increase to 40Gbps data transfer speeds, too.

It won’t happen immediately, however. The USB Implementers Forum (USB-IF) has only just published the specs for USB4, and computers that support it aren’t yet available. The same goes for accessories, though the specification is backward compatible so USB devices made today will be usable with USB4-enabled desktops, laptops, tablets and phones.

Still, USB4 won’t really get started until the later half of 2020.

USB4 is based on Thunderbolt 3

USB4 is getting a head start because it’s based on the Thunderbolt 3 standard already implemented in most Macs. It’s backward compatible with this standard as well, and like Thunderbolt 3 it requires USB-C for its top speeds.

The newest USB version greatly increases the maximum bandwidth compared with earlier ones. USB 3.2 tops out at 20Gbps. The USB-IF designed USB4 to make the jump to 40Gbps. Beyond that, it allows users to connect to data sources and displays at the same time, which will lead to hubs with multiple USB-C ports.

“The primary goal of USB is to deliver the best user experience combining data, display and power delivery over a user-friendly and robust cable and connector solution,” said Brad Saunders, USB Promoter Group Chairman. “The USB4 solution specifically tailors bus operation to further enhance this experience by optimizing the blend of data and display over a single connection and enabling the further doubling of performance.”

USB4 brings two-lane operation to existing USB-C cables, but getting all the way to 40Gbps requires new cables specifically designed for it.


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