USB Implementers Forum (USB-IF), the support organization for the advancement and adoption of USB technology, today announced the publication of the USB4 specification, a major update to deliver the next-generation USB architecture that complements and builds upon the existing USB 3.2 and USB 2.0 architectures. The USB4 architecture is based on the Thunderbolt protocol specification recently contributed by Intel Corporation to the USB Promoter Group. It doubles the maximum aggregate bandwidth of USB and enables multiple simultaneous data and display protocols.

The development of the USB4 specification was first announced in March 2019 by the USB Promoter Group. It is now officially published by USB-IF and available for download here.

AnandTech, who spoke with the USB Promoter Group at Computex, have shared that the new protocol is expected to manifest in physical, consumer products by the end of 2020. The specification for the next-generation bus is currently on version 0.7, with the USB Promoter Group expecting it to be finalized by this Summer. Then it's just a matter of manufacturers developing new products powered by the latest protocol.

USB 4.0 borrows heavily from Intel's thunderbolt 3 technology - which, if you'll remember, was made available as an open specification very recently. Intel's contribution of the Thunderbolt 3 protocol will enable USB 4.0 to achieve speeds of up to 40 Gbps with multiple data and display protocols being able to share available bandwidth. Additionally, USB 4.0 will make use of USB Type-C's interface, ensuring backwards compatibility not only with it, but also USB 2.0, USB 3.0 and Thunderbolt 3. Due to the many improvements in data transfer speeds and ability to stream multiple data and display protocols, the USB Promoter Group is looking at the possibility of changing USB's trademark logo for the next generation interface, alongside a revised branding scheme.