A limiting factor for hosted video, however, is the amount of bandwidth available for video transmission. Bandwidth generally dictates configuration choices like resolution, frame rate and number of cameras that can be deployed. With a local NAS recording option, a user can archive video at a higher resolution and frame rate onsite while lower resolution, lower frame rate video streams to the hosting provider. If the customer sees an event that they want to examine in greater detail, they simply retrieve the higher quality video locally and review the incident. NAS devices can even be configured to regularly upload video to “the cloud” at times of the day when network traffic is low (after hours, for instance) so that it can take advantage of the open and faster pipeline.
This is a solution that dovetails nicely with hosted service providers that offer monitoring services to proactively mitigate risks as they occur. It’s similar to burglar alarm monitoring, except that the provider uses video as the main detection device. In this case, the monitoring company would notify the owner of the business that an alarm was triggered at the back door. The owner would log into the hosted solution, review video and determine if the person who set off the alarm was an employee or an intruder.
NAS as a server-less solution
A third video surveillance niche for NAS leverages the ability of network cameras to stream directly to the NAS device without the need for a server-based video management system (VMS). In its most basic form, the network cameras send video directly to a predetermined file structure on the NAS. From there, a user can view video from the cameras stored in the NAS folder. In this configuration, a small business could deploy a four camera system with a 2TB NAS solution for less than $1,500, delivering HDTV-quality video recordings. In its very basic form, this is a rudimentary solution offering no tools for searching the video or viewing multiple cameras simultaneously - capabilities that are found in even the most basic VMS. If additional functionality is needed, there are other client-based applications that provide a viewer “window” into the stored video on the NAS as well as live streaming from the cameras as a complete small system solution. Some of these applications are sold at app stores or are available free of charge from manufacturers’ websites.
So what are the issues with NAS? Until recently, NAS solutions were generally avoided because the technology wasn’t optimized for the write-intensive nature of video applications. As the use of network-based surveillance systems expanded, NAS manufacturers started developing products specifically designed for video solutions with disk drives that could handle the high I/O requirements and increased write speeds (see recent launches from Iomega and Netgear). But be sure when shopping for a NAS solution that the device you’re purchasing is especially built for the requirements of your system
Detractors of NAS storage solutions commonly cite concerns about NAS storage doubling the amount of bandwidth consumed when used in a traditional VMS model since the video is first streamed to the VMS server and then back to the NAS device. But proper bandwidth estimation and well-planned network design make this a moot point.
The need for cost-effective storage options will increase as more physical security products move to the IP backbone. NAS has been a staple in the IT and consumer industries with a decade of proven performance. As network drive capacities, write speeds and I/O performance continue to advance, NAS solutions will proliferate and become commonplace among security installations.
About the author: James Marcella has been a technologist in the security and IT industries for more than 18 years. He is currently the Director of Technical Services for Axis Communications.