If you buy a USB-equipped gadget today, you'll get the latest USB 3.1 standard, if you're lucky – but the technology isn't standing still. The preliminary specs for the USB4 standard have just been announced, promising a doubling of potential speeds and a range of new capabilities.
Technically, we're now up to USB 3.2 – the specification was drawn up back in 2017, though it's not going to appear in any consumer devices or gadgets until the middle of this year.
USB 3.2 is also bringing with it a revamp of the naming standards, drawn up by the USB Implementers Forum, or USB-IF. USB 3.0 is going to become USB 3.2 Gen 1, USB 3.1 is going to become USB 3.2 Gen 2, and USB 3.2 will be known as USB 3.2 Gen 2x2.
Despite the confusing nomenclature, all you really need to know are the maximum throughput speeds: 5 Gbps for USB 3.2 Gen 1, 10 Gbps for USB 3.2 Gen 2, and 20 Gbps for USB 3.2 Gen 2x2.
That brings us to USB4 (which is apparently dropping the space between acronym letters and version number). Maximum theoretical throughput is again getting doubled to 40 Gbps, which should mean lightning-fast speeds for your external hard drives and other accessories.
The other main headline as far as USB4 is concerned is that Intel's Thunderbolt 3 technology is going to be properly built in for the first time. That means extra versatility in terms of managing data transfer and powering other devices like displays.
For the first time with USB, USB4 will be able to work via a daisy chain of cables, like Thunderbolt 3 can do now – so chargers and displays and drives could be connected with cables rather than relying on a central hub.
The specifics of this are still to be worked out. The USB-IF has only just announced USB4 via the USB Promoter Group (which includes Apple, HP, and Microsoft), and the standard won't be finalized for several months yet. Actual USB4 devices and cables are unlikely to appear until sometime in 2020.
Don't panic though – USB4 is going to be backward-compatible with USB 2, USB 3, and Thunderbolt 3 standards, so all your existing devices will still work (albeit not at maximum USB4 speeds).
Bear in mind that to get full USB4 performance you need both devices and cables that support the standard. USB connector types are usually developed in tandem with USB standards, but are technically separate – so while USB-C will be required for USB4, not all USB-C cables will be USB4-compatible, for example.
"The primary goal of USB is to deliver the best user experience combining data, display and power delivery over a user-friendly and robust cable and connector solution," said Brad Saunders, USB Promoter Group Chairman, said in a press statement.
"The USB4 solution specifically tailors bus operation to further enhance this experience by optimizing the blend of data and display over a single connection and enabling the further doubling of performance."
Source: USB Promoter Group