The next generation of Universal Service Bus (USB) has arrived in the form of USB4. On September 3rd, 2019, USB Implementers Forum (USB-IF) released the documentation of the USB4 specification. For your knowledge, USB Implementers Forum works for the advancement and adoption of USB technology.
The architecture and specification of USB4 are based on the Intel’s Thunderbolt 3 which manages to provide double transfer speed than the existing USB3.2 interface and reaches up to 40Gbps via two-lane operation. USB4 also allows for multiple simultaneous data and display protocols.
You are not going to find something new in USB4 as it is based on the Intel’s Thunderbolt 3 technology. USB4 is capable of sending data over two separate lanes, each lane gets a speed of 20Gbps. Just for comparison with the current USB3.2, it supports 20Gbps two-lane operation with up to 10Gbps per lane.
USB-Type C cable can be used to achieve two-lane operation but a 40Gbps certified cable is needed to obtain the promised transfer speed of up to 40Gbps. Additionally, USB4 is compatible with Thunderbolt 3, USB3.2, and USB2.0. USB4 also makes use of the same USB Type-C connector used by Thunderbolt 3.
In addition to the speed, USB4 has been powered by an upgraded version of USB Power Delivery (USB-PD) extension which makes it possible to charge the device at the rate of up to 100W.
USB-IF has said that they are going to disclose more details about the USB4 and updated USB-PD in coming days. As of now, only the specification of USB4 has been disclosed and we are still unaware of its availability in future desktops and laptops. The real fact is that most of the devices don’t have USB 3.2 port.