What are the Gen 1, Gen 2 and Gen 2 × 2 USB keys?

Finding the fastest USB connection was simple: choose USB 3.0 instead of 2.0. But now you need to know the difference between the USB 3.2 Gen 1, Gen 2 and Gen 2 × 2 models, as well as the definition of the different types of "SuperSpeed".

The USB name used to be simple

Once upon a time, USB was available in two major versions, the 2.0 and the 3.0. All you needed to know about them was that 3.0 was faster than 2.0. You can buy a USB 2.0 flash drive and plug it into a computer with USB 3.0 ports, and it would still work at the slowest speed of USB 2.0. Buying a USB 3.0 drive and plugging it into a USB 2.0 port would also give you USB 2.0 speeds.

If you want the fastest speed you can get a USB 3.0 drive and plug it into a USB 3.0 port. It was simple and straightforward. But everything has changed with USB 3.1.

USB 3.1 has blurred the naming waters

The USB Developer Forum (USB-IF) maintains USB specification and compliance, and hides behind the naming schemes found on USB cables and devices. When he introduced USB 3.1, instead of keeping things simple and letting his name stand out from the USB 3.0, he called the new standard "USB 3.1 Gen 2". USB 3.0 has been retroactively renamed "USB 3.1 Gen 1."

To further complicate matters, the transfer speeds themselves have been given names. The USB 3.1 Gen 1, originally called USB 3.0, is capable of 5 Gbps transfer speeds, called SuperSpeed.

The USB 3.1 Gen 2 is capable of transfer speeds of 10 Gbps, called SuperSpeed ​​+. Technically, it does this by using 128b / 132b coding in a full-duplex communication mode. Full duplex communication is exciting because it means that information can be transferred and received at the same time. That's why it's faster.

The difference between the two was slightly confusing. But, as long as you remember Gen 2 was better than Gen 1, you were ready to go. To differentiate speeds, USB-IF has also implemented logos, which the manufacturer can only use when passing a certification allowing it to prove that a cable matches the promised specifications.

The USB 3.2 is even faster and more confusing

Last September, the USB-IF detailed the new possible speeds for the USB-C and the debut of the USB 3.2 specification. USB 3.2 will be capable of speeds of 20 Gbps. That's twice the transfer speed of the USB 3.1 Gen 2. If you're wondering how the cables double their speed so quickly without changing size or connectors, it's simple. USB products capable of 20 Gbps have two channels of 10 Gbps. Think of it as more wiring stuck in the same cable.

As in previous versions, this new standard is backward compatible for basic use, but you will not get the fastest speed without any new hardware. If you buy a hard drive promising a transfer rate of 20 Gbps and connect it to your current computer, the hard drive will work, but at lower speeds than those provided by the USB ports of your computer. You will need to update both ends of the connection to take advantage of all the new benefits.

At Mobile World 2019, USB-IF announced the marking and naming systems for the new standard. And again, the previous name will be deleted and modified retroactively.

In the future, what was once the USB 3.0, with transfer speeds of 5 Gbps, will be the USB 3.2 Gen 1. The USB 3.1 Gen 2, with its speeds of 10 Gbps, will be renamed USB 3.2 Gen 2.

The new 20 Gbps standard will be named USB 3.2 Gen 2 × 2, breaking the predictable pattern. Physically, this has two channels of 10 Gbps, so it's literally 2 × 2. The name has logic, but it's confusing, and you have to understand the hardware to realize it.

Manufacturers should instead refer to "SuperSpeed"

USB-IF does not want consumers to see these terms. Instead, he wants Gen 1 products to be marketed as SuperSpeed ​​USB. He suggests that manufacturers market Gen 2 products as SuperSpeed ​​USB 10 Gbps and Gen 2 × 2 products as SuperSpeed ​​USB 20 Gbps. But that does not mean that manufacturers have to use these names. Manufacturers can use the Gen 2.2 nomenclature – or if they do not interfere with testing and compliance, they can renounce the logos and use any name.

If the manufacturers comply, the naming problem is quite simple. Look for "SuperSpeed" in the name and check for a number. If you do not see it, it's the slowest type of USB 3.2. If you see a 10 or a 20, it's the promise of transfers of 10 Gbps or 20 Gbps. It could have been better if USB-IF had opted for SuperSpeed ​​USB 5 Gbps for the slowest type. But at least it's pretty simple.

In theory, USB logos should help. As shown in the picture above, the symbols SS and 10 designate this USB cable as a SuperSpeed ​​cable capable of 10 Gbps transfers. Unfortunately, the USB-IF has not yet shown the official certification mark of the USB SuperSpeed ​​20. Presumably, it should be the same logo as above, just with a 20 instead. But we do not know it for sure yet.

If you remember the first problems with USB-C, it will probably sound very familiar to you. Read carefully before buying cables and buy them from reputable and reputable sources. In the past, we recommended Amazon Basics cables – but even with those, you should always look carefully. For example, this Amazon Basics cable is USB-C but offers only 2.0 speeds. This Amazon Basics cable, which looks almost the same, offers 10Gbps transfers and is marked USB 3.1 Gen 2. And of course, this does not apply only to USB cables. This applies to any hardware using USB-C.

Unfortunately, this remains a jumble of confusing terms. When you buy USB hardware, you need to do your due diligence to know exactly what you are buying.