USB Forum and Intel Team to Build USB 4 on Thunderbolt 3

The USB Implementers Forum (USB-IF) has introduced USB 4, which doubles the maximum speed to 40Gbps or more over certified cables. That throughput could power two 4K displays, one 5K display or an external graphics card. It does this via a new transfer scheme that uses existing USB Type-C cables to tap two lanes and supports numerous data and display protocols that more efficiently parcel total available bandwidth over the bus. Most importantly, USB 4 will be built on Intel’s Thunderbolt 3, ending competition between the two.

VentureBeat reports that USB 4 is “backward compatible with USB 3.2, USB 2.0, and Intel’s Thunderbolt 3 technology and will be able to deliver up to 100W of power.” “The USB 4 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,” said USB Promoter Group chair Brad Saunders.

Among the similarities USB 4 shares with Thunderbolt 3 are “simultaneous data transfer and speeds of up to 40Gbps.” The biggest difference is that USB 4 is an open standard and Thunderbolt 3 is proprietary — currently royalty-free, but still requiring manufacturers to obtain certification.

Still, Intel is wary of giving up on Thunderbolt 3 for a simple reason: USB-IF “doesn’t impose mandatory requirements” on those that adopt USB 4, which means it is likely to be implemented inconsistently. Intel’s Thunderbolt is currently part of the design of “over 400 PCs and 450 docks, displays, external graphics enclosures, and storage from HP, Apple, Asus, Lenovo, Dell, and Huawei.”

Intel client connectivity division general manager Jason Ziller noted that the company released the Thunderbolt protocol specifications in collaboration with the USB Promoter Group, calling it “a significant milestone for making today’s simplest and most versatile port available to everyone.”

Before the USB Developer Days conference convenes in Vancouver, the USB-IF and 50 companies working on the USB 4 drafting process are “working towards finalization” of the standard.

Wired reports that the USB-IF confirmed that, “USB 4 would be built on Intel’s Thunderbolt 3 instead of competing with it as it had previously done.” With downloads of 40 Gbps, Thunderbolt 3 can “handle multiple display and data protocols at the same time” and be of use to the growing “creative class.”

“The data density from data like video have increased,” said Moor Insights & Strategy founder Patrick Moorhead. Despite the announcement about USB 4, USB-IF still plans to “roll out three tiers of performance before USB 4 materializes: USB 3.2 Gen 1, USB 3.2 Gen 2, and USB 3.2 Gen 2×2.”

Although USB 4 and Thunderbolt will be a converged environment, the “madness” won’t be entirely over, because “Intel will continue to develop Thunderbolt 3 independent of USB 4, and there’s no guarantee the two protocols will progress in lockstep from here.” “It’ll be up to the USB working groups to decomplexify the verbiage,” Moorhead says. “I’m not optimistic, as the group has created pandemonium in the past.”