MWC 2019 sees the USB Implementers Forum (USB-IF) present a rebranding of the USB 3.0 standard-- the upcoming USB 3.2 will absorb prior USB 3.0 and 3.1 specifications, leading to a perhaps confusing take on USB classification.
Essentially both USB 3.0 and 3.1 will now be considered as generations of the USB 3.2 specification. Thus USB 3.0, which offers speeds up to 5 Gbps, is now USB 3.2 Gen 1. Meanwhile USB 3.1 Gen 2, with support for transfer rates of up to 10 Gbps, becomes USB 3.2 Gen 2. As for what we know as USB 3.2, with throughput reaching 20 Gbps, the standard is designated as USB 3.2 Gen 2x2.
In order to prevent consumer confusion, the USB-IF recommends an alternative nomenclature-- “SuperSpeed USB” for 5Gbps products, “SuperSpeed USB 10Gbps” for 10Gbps products and “SuperSpeed USB 20Gbps” for 20Gbps products.
USB 3.2 Gen 2x2 uses up to two high-speed 10 Gbps channels in order to achieve transfer rate of 20 Gpbs. It serves as both an upgrade to the USB feature set and a physical layer tweak providing more bandwidth. That said, since conventional USB hosts and devices are designed as single-lane solutions, USB 3.2 Gen 2x2 is only possible over USB-C connections.
The USB-IF says discrete USB 3.2 controllers capable of supporting the 20 Gbps mode will be available later in 2019.
