The group of companies for the development of USB, which includes Apple, HP, Intel, Microsoft and other corporations, has announced a new USB standard 4, which is soon to replace the current specification. That’s just in fact it is already existing Thunderbolt 3, just with some changes.
USB 4 is a major update for the USB architecture of the next generation, which is based on existing specifications USB 3.2 and USB 2.0. It is based on the Protocol ThunderboltTM, recently introduced by Intel. It doubles the bandwidth of USB and allows you to use multiple protocols for simultaneous data transmission.
Despite the fact that the specification USB4 introduces a new underlying Protocol, support previous USB standards 3.2 USB 2.0 will not go away. Features of the updated USB is an effective rate of 40 GB/s and backward compatible with Thunderbolt 3, and with earlier versions of USB (up to USB 2.0). The physical connectors are the same as the USB-C which are used for Thunderbolt 3, which means that all existing Thunderbolt cables 3 should work with the new specification.
Backward compatible with Thunderbolt 3 also means that USB 4 supports the same options of “delivery” of energy. In other words, the owners of the new MacBook (up to 2018) already have access to new technology, only under a different name.
The final specification should be confirmed by mid-year, but given the statement about the compatibility, significant change is unlikely. USB 3.2 will appear in devices later this year, offering bandwidth up to 20 GB/s. But this is the maximum, so in fact it can be 5, 10 or 20 GB/s.
As for USB 4, The Verge reports that since the approval of the final specifications, which will be published in the second half of this year, and the appearance of the first devices on the market, will be 18 months. So we are waiting for his arrival until 2021. By the time the MacBook Pro will have the same capabilities with Thunderbolt 3 for five years.