Recently, Drive Rescue were in Nuremberg, Germany, attending EmbeddedWorld 2019. While this event primarily caters for electronic systems, edge computing, IoT and energy efficiency, it also hosts a number of storage device manufacturers.
NAND, NAND, NAND – it’s everywhere
In fact, one could hardly walk 20 metres in the exhibition halls without encountering NAND memory in some form or another, from either systems integrators or the manufacturers themselves. The latter were displaying NAND in more visible forms, such as in USB devices and SSDs.
From Industrial machines to torpedoes
The affable team from Transcend explained how their NAND-based memory products are widely used in everything from industrial machinery, slot machines, robotics to torpedoes. These are areas not normally associated with “boring” storage. Transcend are suppliers to Kuka, one of the world’s largest robotics manufacturers, whose robots are used in everything from car manufacture to nuclear decommissioning.
High-quality NAND is essential in applications such as these – for example, a robot will constantly read and write to NAND memory. (Transcend recommends using its “SuperMLC” NAND, which is MLC memory designed to emulate the reliability of SLC, for uses such as these.) Likewise, durable NAND is essential for medical devices that use logging capabilities, such as heart rate monitors. I asked the Transcend team what sets them apart from the competition and the emphatic answer was “quality control”.
What butchers and NAND suppliers have in common…
Transcend source NAND wafers from either Samsung or SanDisk. A wafer is like a large sheet of NAND. The best quality NAND chips (or prime cuts) are in the centre with the lower-quality NAND chips (offal) residing at the fringes. Transcend only use prime cuts of NAND for their memory products. (Low-quality NAND probably ends up in generic USB sticks sold on eBay or in SD cards sold in street markets.) Once cut. the company use an extensive four-stage testing process to weed out any defective NAND. This is important if your NAND is being used for torpedo guidance systems. However, even with stringent quality control processes, people still lose data. The Transcend team explained how human error is the biggest cause of failure for their SD cards. For example, they manufacture consumer-level dash cams. For those motorists unlucky enough to be involved in an accident, their first instinct is to seize evidence of the event. So, with their dash cam still running, they pull the card out and, ironically, end up corrupting the very information they want to preserve. Murphy’s Law in extremis.
And talking of data preservation on NAND, the Taiwanese SSD manufacturer ACPI sees sudden power loss as a major issue for industrial PC, enterprise servers and professional grade photo systems. This can still occur even with a UPS deployed. For this reason, ACPI has brought out its “Power Shield” technology for its SSDs. This protects a data write even during total power loss. Capacitors store a residual voltage which enables any tunnelling electrons in the floating gate to reach their destination safely.
Sony enters the consumer and industrial SSD market
Sony was a surprise exhibitor at EmebeddedWorld 2019. While not normally associated with SSDs, it has been dabbling in solid-state storage for quite a while. (Primarily sourcing its NAND from Toshiba and controllers from Phison.) Sony’s USB memory sticks and SD cards have been on the market in Ireland for a number of years. Many readers of this blog might be familiar with its distinctive “Memory Stick Duo” cards that were first introduced on the market circa 1998, in the nascent days of digital photography. Those involved in professional TV and film production who use Sony kit will probably be familiar with its SxS cards for professional grade camera equipment. These cards, now called SxS Pro+, are still being produced by Sony and offer capacities of up to 256GB, offering write speeds of up to 400MB/s. For commercial/industrial customers, Sony now offers a range of M.2 SSDs optimised for heavy-duty use. It will shortly be introducing external SSDs for the consumer market with USB-C interface and capacities of up to 960GB.
Toshiba – the inventors of NAND
Before floating-gate technology was invented, semiconductor design had to rely on EPROM and EEPROM. But both of these technologies were relatively slow and could only store the most basic of information. That was until 1984, when Fujio Masuoka of Toshiba came along and wrote a research paper on a revolutionary type of memory design called NAND. Toshiba’s first NAND went to market in 1989 and the rest is history. NAND has been getting denser, faster and more capacious with every new iteration.
3D NAND Fever
The current iteration of NAND that Toshiba is marketing is its 64-layer 3D BICS NAND. One of the Toshiba team described how the market is now in a state of “3D fever, as everyone wants a piece of the 3D NAND action. Toshiba is currently using 15nm 64-layer 3D TLC “Bics” NAND in the majority of its SSD devices. According to Toshiba, its “charge-trap” technology is more reliable than “floating-gate” (which is actually a technology from the 1970s). The latter transistor design holds electrons like “water in a glass”, whereas “charge-trap” technology is “more like a sponge”. The electrons are less likely to leak and, therefore, more likely to maintain the integrity of your data. The next iteration that Toshiba expects to commercialise is its 96-layer 4-Bit QLC NAND later on this year.
Although Toshiba is known for inventing NAND, they still manufacture mechanical hard disk drives. (In fact, Toshiba’s hard disk and SSD operations have now been spun into two separate divisions). With the current trend for Big Data analytics and virtualised storage systems, Toshiba is adapting its product lines. For example, its “AL” series of disks are designed for use in Tier 1 enterprise servers. These disks use a SAS interface and have capacities of up 2.4TB with a MTTF of 2 million hours. Toshiba’s “MG” series caters for enterprise storage arrays. The MG07 and MG08 can hold up to 14TB and 16TB of data respectively. These whopping storage capacities are achieved with the assistance of helium, which is injected into the main chamber of the drive. This is then laser-sealed. Helium enables smoother writes that are closer to the platters and reduces power consumption. Moreover, these disks contain 9 platters instead of the competition’s 8. (We’re glad to see that Toshiba is not skimping on platters. As a data recovery company, we know what can happen when manufacturers try to economise on them… Seagate’s calamitous “DM” series of 3.5” disks being a prime example). This series of disks also use MAMR (Microwave Assisted Magnetic Recording) whereby a Spin Torque Oscillator of frequencies between 300GHz and 300MHz saturates the bit areas of the platter with a concentrated microwave field, which enables more reliable writes in high-density disks.
Scaling up this technology means that we might be seeing 28TB or higher capacity HDDs in the not too distant future. It will be interesting to see what approach Seagate will adopt with its disk-heads as its HAMR technology has come in for sustained criticism for stressing disk platters (not to mention the users…) For non-data centre disks, Toshiba also makes disks for the SME and personal market. Its N300 disks, designed for NAS, come in sizes of 4-14TB, designed for 24/7 usage. Toshiba also makes standard mechanical disks, such as the P300 (3.5” S-ATA) and L200 (2.5” S-ATA).
Maybe it’s all the crime thrillers that people are watching on Netflix or the Dublin gangland documentaries being shown on Virgin Media One, but there’s been an explosive growth in home surveillance systems in Ireland recently. Similar trends are occurring worldwide and hard disk manufacturers are responding to this demand. WD already has its “Purple” disks, Seagate its “Skyhawk” line-up and Toshiba its “S300” surveillance hard disks. This disk (picture above) comes in capacities of 5TB to 10TB and is designed for 24/7 operation. It’s a “write-centric” disk, meaning that its disk-heads and firmware are optimised for 90% writing and 10% reading.
According to the NAND and SSD manufacturer Micron, this growth can be partially explained by the precipitous drop in prices for 2K and 4K image sensors (a key component of camera manufacture). But growth in surveillance is also being boosted by the next-generation SOC (system on chip) security systems, which use deep learning and AI (Artificial Intelligence). Where once security systems or facial recognition technologies would just capture and store, now they can capture, store and analyse. This was presciently portrayed in the James Bond movie The Living Daylights (1987), where the baddie Max Zorin used facial recognition technology in his office to identify James Bond in a matter of seconds. Surveillance systems now need to perform analysis in real-time without the latency incurred by communicating back to a centralised cloud-based server. Imagine an AI-powered surveillance system in an airport that detects a passenger at the boarding gates who is on a “no-fly” list. Even with a relatively fast link to “the cloud”, image retrieval and analysis might still prove too slow. If that same surveillance system used edge-based SSD storage, the storing, analysis and processing of images of the system would be vastly accelerated.
In use cases such as these, NAND is the big enabler. A body or dash camera using a 2.5” spinning disk would probably not last too long in the field. While NAND has been on the market for a relatively long time now and its evolution to layered versions or “3D” means we now have higher capacity reliable storage in a very small form factor. Micron was exhibiting its “C200” microSD card which was released at the Mobile World Congress in Barcelona just a few days previously. This Lilliputian card uses 96-layer 1TB QLC 3D NAND with eight 128GB dies. It has write-speeds of 100MBps and read-speeds of 95MBps. If Micron can scale its NAND to 256-layers, I’ve no doubt that we’ll be seeing 2TB and 4TB versions of this card shortly.
Now you might be thinking, does the average consumer really need 1TB of storage in their camera or phone? Well, a substantial number of consumers now expect to be able to shoot footage on their phones or action cams in 4K HDR quality. (To give this question some perspective, only twenty years ago phone manufacturers were asking themselves, do consumers really need cameras on their phones at all?)
While a card like the “C200” might be fine for a consumer-level smartphone or action cam, it might not be the ideal solution for other use cases. For instance, the primary storage in edge-based surveillance systems is often in the camera itself. (Having the storage here eliminates the network congestion that is generated by IP-based cameras and frame loss due to network disruption). The storage medium in such a camera means it is going to be exposed to constant writes. This is something that a QLC-based NAND card would not be able to do! For this, reason Micron has brought out industrial-quality TLC-based SD cards using 3D NAND (such as the MTSD256AHC6MS-1WT). Its high-capacity models can store footage for up to 30 days and come equipped with a card-lock to prevent tampering. Micron also offers a health management API to proactively warn system administrators of potential SD card failure.
The future of computing is edgy…
It’s not only in surveillance that edge-based storage is playing out. IDC Research estimates that in the next 3 years, 45% of IoT generated data will be stored, processed and analysed at the edge of the network. And this is something that NAND and SSD manufacturers are extremely interested in. Edge Computing offers faster response times, more reliable operations in areas of poor internet connectivity and better data security. Most Android smartphone users that use Google Maps’ “offline maps” feature know the benefits of having local storage. It’s often significantly quicker than the device having to communicate with the cloud. It is being touted that autonomous cars are basically going to be “servers on wheels”. It is inevitable that these cars will traverse areas where internet connectivity is poor. Here SSDs and NAND will play a pivotal role in not only mapping, but also enabling the execution of the car’s key software functions.
The pervasiveness of high-speed high-capacity is going to make our lives easier. Ever tried to buy a train ticket from a self-service kiosk on a busy rail network at peak time? You have probably noticed that the loading of the menus and timetable information is laboriously slow. It’s more than likely that the ticketing machine, along with hundreds of others, was simultaneously communicating with a central server and the network was congested. Taking an “edge computing” approach to this problem, key information, such as timetable information, is stored locally on the ticket machine (just like Google “offline maps”) while data, such as real-time updates and seat availability, are transmitted in the form of compact, computed findings rather than raw information. Or let’s take the example of a wind farm off the west coast of Ireland. While it’s probably still within connectivity reach of 3G or 4G networks, constant communication might be more problematic. Storage on the “edge” can mean there is no data loss or operational failure in the event of limited connectivity. This is not to say that the Cloud is going to become redundant, but it will take a more passive role in our lives – partly enabled by advances made in NAND memory technology. Thank you, Mr Masuoka!
Drive Rescue Data Recovery is based in Dublin, Ireland. We offer a complete data recovery service for SSDs such as those from Toshiba, Samsung, Micron (such as 1100 M.2, M500 and M550) and SanDisk. We also recovery from Toshiba portable hard disks such as the Toshiba Canvio (DTB320, DTH 305, DTH310 and DTH320) and recover from disks such as inaccesible WD My Passport Ultra portable disks with blinking lights. Find out more at: www.datarecoverydublin.ie