Just got used to USB 3 in all its diversity? Good news, the spec for USB4 has just been released!

Industry body USB-IF promises double the speed and sensible naming conventions

The final specification for USB4 has been released by industry body USB-IF.

The industry body described USB4 as "a major update" adding that it "builds upon the existing USB 3.2 and USB 2.0 architectures".

First announced in March 2019, USB4 is based on the Thunderbolt protocol specification recently contributed by Intel to the USB Promoter Group, and promises to double the maximum aggregate bandwidth of the USB standard.

Key benefits of USB4, according to USB-IF, will be:

Notably, perhaps, the standard will retain the USB-C one-cable-fits-all physical connectivity, splitting data transfer and power delivery in a way that's easier for the machine to differentiate, and assign power appropriately between multiple devices in the same port.

However, it will take some time before USB4 is supported in cables, ports, PCs and devices, with 2020 or even early 2021 when the first products will have been designed, manufactured and finally appearing on sale - no doubt on Alibaba or Amazon first. In the meantime, USB-IF will continue to promote USB 3.x, with USB4 pitched as a premium product.

Furthermore, in a bid to avoid confusing the market, as it did with USB 3.0, 3.1 and 3.2, USB-IF promises to refrain from such sub-branding USB4. In other words, you will only find USB4 all the way until a USB5 specification is thrashed out, and that ought not be before around 2025.

USB-IF was strongly criticised earlier this year for the confusing nature of its branding, and the various arcane differences introduced between USB 3 specifications, which the vast majority of consumers would not understand. Adoption has suffered as a result.

Whether USB4 sticks ever turn up or not, is open to questions, according to the inventor of USB himself, Dov Moran.