One port to rule them all.
For almost two decades now, the Universal Serial Bus (USB) port standard has likely been the most commonly used connection technology in the world.
Developed by the USB Implementers Forum (a group of major IT companies), the USB is a plug-and-play interface, which is used to connect a computer to a wide variety of devices – from storage to input hardware. The reason why USB became so popular is because it replaced many older interfaces and thus standardised and simplified the connection of peripherals to personal computers, both to communicate and supply power. Subsequently, the standard was also adopted in many other devices, such as smartphones, tablets and video game consoles.
For some time, it was fairly easy to make sense of the different USB specifications and the most commonly used connector types. But as technology evolved and new devices emerged, things got more complicated – the USB has expanded into multiple versions with different connection speeds and many types of cables. A port that was once designed to simplify things was not so simple anymore, and people started to get confused about the many terms attached to it. The USB Implementers Forum once again tried to solve this problem with the introduction of the USB Type-C, but while the new connector is ultimately beneficial, many still do not understand what Type-C stands for and how exactly is it better. Therefore, we intend to provide you an overview of how the USB evolved over time, in order for you to understand what the latest technology in this domain is aiming to offer.
First of all, let’s clarify the meaning of two different terms that describe the Universal Serial Bus: the standard (or specification) and the connector type.
The USB standard is the protocol that specifies how the data transfer and power supply are managed, meaning what the USB connection can do in terms of speed and feature improvements. The USB connector, on the other hand, is the physical shape of the port in your device and of the cables that plug into it. So, we’ll take a look at all the different standards and connection types to help you understand the benefits and limitations of the various USB technologies. Eventually, we’ll explain what USB Type-C means and why it is a game changer.
USB 1.1 (Full-Speed USB)
Released in August 1998, this is the first USB standard to be widely adopted (the original version 1.0 never made it into consumer products). The USB 1.1 had a maximum speed of 1.5MB/s (12Mbps) or 0.1875MB/s (1.5Mbps) for peripherals like keyboards and mice. Not all accessory makers made the switch to USB right away, but keyboards, mice, and printers among others began to include USB ports and connectors as an option, and later as the primary interface.
USB 2.0 (Hi-Speed USB)
The second version of USB arrived in 2000 and it provided a massive boost in maximum data throughput – 60MB/s (480Mbps). This increase in speed made the specification suitable for use with external hard drives and other types of data storage devices for the first time. USB ports began to multiply and completely replace older legacy ports on desktops and laptops. USB flash drives started to replace floppy disk, CDs, and DVDs.
USB 3.0 (SuperSpeed USB)
Released in 2008, the USB 3.0 provided an unprecedented increase in transfer speeds of up to 500MB/s (5Gbps). It improved upon the USB 2.0 technology not only with speed and performance increases but also superior power management and increased bandwidth capability (providing two unidirectional data paths for receiving and sending data at the same time). A USB 3.0 port and connector is usually coloured blue and is backward-compatible with USB 2.0. More recently it is also referred to as USB 3.1 Gen 1, for the reasons which we’ll explain later in the article.
USB 3.1 (SuperSpeed+ USB)
USB 3.1, also referred as USB 3.1 Gen 2, is the very latest version of the USB standard. It was introduced in 2013, and not surprisingly, its main benefit is the improved speed of up to 1.25GB/s (10Gbps), making it as fast as the original Thunderbolt standard. More, the USB 3.1 has three power profiles and allows larger devices to draw power from a host: up to 2A at 5V (for a power consumption of up to 10W), and optionally up to 5A at either 12V (60W) or 20V (100W). Because of this, the USB connection can be used now to even charge a laptop.
The Type-A is the classic and most widely recognised USB connector which works with all USB specifications. Its fundamental designed has remained the same over the years and it became the standard plug for use at the host end of the USB cable and in data storage devices. The connector went only through a number of small changes to accommodate different versions of USB. For instance, more pins were added to allow for the faster speeds of USB 3.0, but the changes were incorporated in such a way that all USB Type-A plugs and sockets are compatible no matter which standard of USB they use. Type-A mini and micro connectors also exist but are incredibly rare. Neither of these were updated with 3.0 versions.
While the Type-A is one end of a USB cable that connects to the host, the other one, which links to the client, uses a USB Type-B connector. Because there have been so many different devices out there, the Type-B comes in more variations. The original Type-B plug was used for printers, but many of you might be more familiar with the Type-B miniUSB and microUSB cables. Nearly all modern smartphones, aside from the iPhone which uses a proprietary Lightning charger, charge via a 2.0 Type-B microUSB. There is also a Type-B microUSB that uses the 3.0 standard, but the connector has a different shape, with an extra plug that carries more power.
Finally, the new USB Type-C, developed at the same time as the 3.1 Gen 2 standard, is the connector that intends to replace both Type-A and Type-B and eliminate the need for any mini or micro variants, since it’s small enough to work for even the smallest peripheral devices. This means you will have a universal cable with the same connectors on each side, which are also symmetrical so you don’t need to worry about plugging it in upside down as it will function both ways. One reversible cable for charging and data transfer for all your devices and the same simple port on your smartphone and laptop is great, right? But the benefits do not stop here. Because the USB Type-C was built as a native connector and port for the USB 3.1 Gen 2 standard, it can fully take advantage of the exceptional data transfer speeds of up to 10 Gbps (that’s assuming that you have the correct ports and cables on both ends, and that both the reading device and writing device can transfer data at that rate). Note that USB Type-C is also compatible with the USB 3.0 standard, this is why the USB Implementers Forum renamed it as USB 3.1 Gen 1, and the 3.1 standard as the USB 3.1 Gen 2 – to emphasize their similarities and compatibility with the new connector type. So when you’re shopping for a new product that includes a Type-C connector, check if it has USB 3.1 Gen 1 or Gen 2 specifications.
Another benefit of USB Type-C is that it allows for bi-directional power, so apart from charging the peripheral device, when applicable, a peripheral device could also charge a host device. Also, thanks to higher data throughput, USB Type-C cables can be used to deliver video as well. USB 3.1 Gen2 supports the MHL 3 specification, which can output video at up to 4K resolution. So potentially the USB Type-C could replace current standards and ports like HDMI, DVI, and DisplayPort.
In conclusion, the USB Type-C connector aims to simplify how we manage data transfer, charging and even video streaming between our devices. However, there is one small downside for now – we’ll have to use adaptors for our current cables and devices (in case it only has USB Type-C ports) since not all manufacturers are adopting the standard and connector at once. But the future really seems to be about one cable and one port to rule them all, which hopefully should be to everyone’s advantage.