Why edge storage has become more mainstream

Just like edge computing, edge storage is also gaining momentum among users of video surveillance systems. Amid this trend, using surveillance-grade memory cards optimized for constant writing and recording has become critical, too.
 
In video surveillance, storage typically takes the form of recording video to a server/NVR onsite or in the cloud. While effective, this architecture has certain disadvantages. “Onsite installation of NVR, networking equipment and VMS software are expensive. Maintenance of IT equipment and monitoring are also costly and are not core competencies of most small businesses,” said David Henderson, Director of Industrial and Consumer Segment Marketing under the Embedded Business Unit at Micron.
 
As such, more and more attention has been focused on edge storage, namely recording video to the microSD card in the camera. While edge storage has long been used as a backup solution – the camera saves to the microSD card only when the network goes down or becomes unstable – it has increasingly become the primary source of storage, thanks to its various benefits and technology advances.
 
“We know that advances in nonvolatile memory technology have enabled edge models that drive cost and performance advantages,” Henderson said. “Because primary video footage is stored locally in the camera, these systems require less network bandwidth and avoid cloud storage costs, offering better scalability and TCO compared to cloud only storage solutions. These benefits make edge storage a preferred choice for many system integrators and end customers.”  

How to Select the microSD Card

To get the most out of edge storage, a surveillance-grade microSD card optimized for 24-7 recording should be used. “The major differences (between consumer-grade and surveillance-grade microSD cards) are the NAND flash technology used in the card, how well the firmware is optimized for 24/7 video recording and how the NAND is tested and screened to improve overall product reliability,” Henderson said. “A common mistake today is the use of consumer-grade microSD cards in video surveillance deployments. Recording to a consumer-grade microSD card for 12 or more hours a day, the memory card will likely fail within months of deployment.”
 
How, then, should the user select an industrial-grade microSD card? Henderson suggested the following criteria to look for.
 
Storage capacity: Is the edge storage solution able to store up to 2 weeks, or even 1 month of video archives (at the target resolution with the chosen compression techniques)? With continuous recording of high-quality surveillance video, the user will need a higher density storage device to meet data storage and archiving requirements.
 
Endurance and quality: Will the edge storage solution have the rigor and design longevity to last three or more years in the field? The typical surveillance solution needs to be ruggedized, even all weather-resistant. To reduce maintenance and decommission costs during service years and control TCO, a high-endurance device with surveillance grade edge storage is essential to avoid costly onsite service and truck rolls to replace failed cards.
 
Recording performance: Does the edge storage solution meet the user’s service level agreement (SLA) for data quality? Continuous video recording into a storage device can cause frame drop issues. The edge storage device must optimize its recording performance for surveillance usage to reduce the risk of data loss.
 
Citing his own company’s example, Henderson said Micron’s industrial microSD cards are specifically designed for IP video surveillance workloads and feature the following: storage densities of 32GB, 64GB, 128GB and 256GB allowing for – if certain conditions are met – three years of continuous, 24/7 video recording and a two million hours mean time to failure (MTTF); special firmware that minimizes frame drops and video capture; and technology for the cards to self-monitor and provide information on card usage and expected useful life remaining for each card.