The official Thunderbolt-based USB4 specification is complete, the group that designs it announced on Tuesday.
USB4 is the next major version of the USB, which gains a major speed boost thanks to Intel licensing its Thunderbolt 3 protocol to the USB Promoter Group on a royalty-free basis. This group includes Apple, HP, Intel, Microsoft, and Texas Instruments.
USB4 will enable 40Gbps speeds equivalent to Thunderbolt 3, which is currently found in high-end computers like the MacBook Pro and peripherals.
That’s twice as fast as the current USB 3.2. However, as noted by CNET’s Stephen Shankland, many consumers are still using computers with earlier versions of USB that offer 5Gbps or 10Gbps.
Thunderbolt 3’s incorporation into USB4 should bring higher speeds to lower-end devices and peripherals. And those higher speeds will be useful for connecting multiple displays and getting data from external hard drives.
The longer-term promise of the speedier USB4 is that device makers will stop using old rectangular USB-A ports and USB Micro B ports in favor of the newer USB-C connectors, which USB4 requires to work.
The USB Implementers Forum told CNET that consumers could expect to see devices, including laptops, external hard drives, and dongles with USB4 support in the “second half of 2020”.
USB-IF notes three key benefits of USB4:
- Two-lane operation using existing USB Type-C cables and up to 40Gbps operation over 40Gbps certified cables
- Multiple data and display protocols that efficiently share the maximum aggregate bandwidth
- Backward compatibility with USB 3.2, USB 2.0 and Thunderbolt 3
Beyond speed, Thunderbolt technology is helping USB4 simultaneously handle video signals for external monitors and TVs, as well as data going to and from external hard drives.
That means USB4 can be used for driving multiple displays simultaneously and multiple data applications over a single link. Additionally, as Thunderbolt does today, it will let consumers plug in external graphics cards to boost graphics on laptops.
Despite Thunderbolt 3’s inclusion in USB4, Shankland notes Thunderbolt 3 is an “optional capability” for USB4. So while Thunderbolt 3 on today’s MacBook Pros uses its USB-C ports, a future USB4 port won’t necessarily support a Thunderbolt peripheral.
Also, USB devices must include USB Power Delivery, which allows for high charging rates to support laptops.