You can’t keep a good USB drive down.

Despite the ubiquity of cloud-connected storage and the ever-increasing capacity on smartphones, laptops, and desktop computers, USB storage shows no sign of disappearing and it is also finding new uses cases.

Small flash drives are still a popular handout at conferences because they can include marketing information as well as a link out to more information, said Thomas Coughlin, founder of Coughlin Associates, who spoke to EETimes via telephone at such a conference. “There are also people who would rather keep their information not on their computer but on something that they control more.” One scenario might be to archive a large amount of data on a drive and then place it in a safety deposit box.

Spinning disks still dominate the portable USB storage market, he said, but as flash prices come down and portable density goes up, there is a growing demand for rugged USB flash for people on the go — despite the growing storage space in smartphones, which is approaching as much as one terabyte of onboard storage in some models.

Clinton Lee, senior manager of marketing for SanDisk-branded products at Western Digital, said people still need to offload or even back up files that they've captured with their smartphones, particularly high-quality content such as high-resolution photos and 4K video. “People capture images on their smartphones, but they want to back them up on portable storage,” he said. “It's like the old days when flash drives originally came out or were introduced to support your computer — moving content from computer to computer, sharing content from one to another.”

Lower costs and higher flash capacities are enabling USB drives such as Kingston’s DataTraveler Ultimate GT to provide storage of up to two terabytes.(Source: Kingston Technology)

The development of USB technologies, regardless of type, is making it easier and faster to transfer large files off portable devices, often faster than network options that can cost a smartphone user money, or when there is no internet available, said Lee. Professional photographers, for example, need secure portable storage that's not only reliable but also durable. “They prefer to back it up onto a portable source and free up memory on their cameras.” Once they get back to the office or hotel room, they can edit those photos, prepare them, and send them off to publishers.

Lee said a lot of USB flash offerings are about helping consumers move high-quality content — not just from their smartphones, or computer to computer, but to any device that has a USB port. “It could be your TV, or a gaming console, or taking a photo from one device to your printer to print. There are so many use cases. As long as there's a USB port, there's always going to be a need for a USB-type solution.”

While mobile devices have increasingly larger internal capacity and offer faster and more convenient cloud storage options, USB drives still play an important role for enabling fast and direct attached storage expansion, said Robert Allen, European director of marketing & technical services at Kingston Technology. Kingston EMEA has seen a 42% year-over-year increase of units sold across its commodity USB sales, while the smartphone industry is reporting a year-over-year decline, he noted. “It’s more cost-effective to turn to external storage solutions rather than to upgrade your device.”

Allen said sales are being aided by decreasing costs of flash, which is reflected in customer buying behaviors (including consumer and small and medium-sized business market segments). The move from planar 2D NAND to multi-layer 3D NAND has lowered costs and increased densities, he said. “This enables large portable storage devices to be more affordable than before, as gigabyte cost continues to decline.”

The ever-present cybersecurity climate will spur use of encrypted USB and SSD

There is a healthy market for rugged and fast portable USB drives, such as the SanDisk Extreme PRO Portable SSD, which is for creative professionals who want to move massive files quickly and do realtime editing directly from the drive. (Source: Western Digital)

It’s not just the media itself that’s keeping USB drive sales healthy — it’s the USB connectivity. Allen said an area for growth is the post-General Data Protection Regulation (GDPR) era and the ever-present cybersecurity climate that’s spurring use of encrypted USB and encrypted SSD offerings. “USB/SSD encryption is one of the most trustworthy means of protection, especially in cases involving confidential, personal, or even sensitive data.” He said it’s particularly cost-effective for most organizations because it doesn’t involve cultural change, substantial training, or user adoption — like some of the alternative cloud options. “You simply replace all the USB drives with encrypted drives and whitelist them, preventing any other device from logging into the network.”

Coughlin said fast connections such as USB-C are appealing to people who want quick access to data and who don’t want to put it on a network. Keeping drives off the network also gives users an “air gap” that isolates it from networked storage that might get infected by viruses and malware. “It gives you a better chance of not getting your data compromised.”

The USB-C and the new USB interfaces are not just for enabling data transfer for storage, added Coughlin. “They also carry power and there are people that are showing display devices running off USB, for example. If you look at the new Macs, they use USB-C for power connection. It has essentially become a common external interface, but also a power connection for a lot of technologies. It’s not going away any time soon.”

In fact, USB is creating opportunities for external flash drives in industrial applications, including the tried and true thumb drive, which can be used to boot-up a virtualization engine or a hypervisor, said Scott Phillips, vice president of marketing at Virtium. “It's basically running an environment for that server.” Another use case is engineers loading firmware or other software updates on to a remote device in the field.

USB4 standard will lead to larger capacity, higher performance

Another use case is embedded, said Phillips, which often implies an integrated storage device — but many systems have a 10-pin header with one that’s clipped, which allows for a USB module to be plugged down onto nine pins. Not much larger than a postage stamp, with capacities into the 64-gigabyte range, these devices are primarily used for booting, he said, and quite rugged so as to handle shock and vibration well. It’s also a low-power option, coming in at half a watt or less. It’s not meant to be high performance, but it’s ideal for gathering sensor data, for example.

Combine USB with the M.2 form factor, said Phillips, and you’ve got a low-power, small-footprint alternative to SATA and NVMe which are more power hungry and hence produce more heat. Virtium’s customer base tends toward embedded scenarios involving small, sealed boxes with no airflow. “High heat is the enemy of electronics, so we gave them alternatives.” This keeps the door open to move to a SATA or NVMe interface, he said. “You just route the signals on the host connector to the same mechanical format and plug this one in, so you don't have to change your physical board dimension or change anything.”

USB may not be as fast as SATA, but the later generations give it a run for its money with higher bandwidth, said Phillips, while maintaining backward compatibility, which is important to some customers, such as those in telecom. Looking ahead, there are IoT and factory automation applications that require increasing amounts of storage, he said, and one option is doing an external ruggedized USB box not much bigger than a cellphone. “It’s very interesting to bridge current mainstream technologies like NVMe and USB.”

Kingston’s Allen said the work of the USB Promoters Group and the USB4 standard will lead to larger capacity portable storage devices with higher performance characteristics. “The NVMe standard unlocked the performance potential for SSDs,” he said. “New technologies like USB4 and SD Express will bring benefits of flash storage further.”