Remember the days when your surveillance system was a handful of analog cameras and a clunky VCR?
Those times were simpler, but video cassettes have gone the way of 8-track tapes and floppy disks.
Today’s security systems have the same sophistication as your building automation system.
While security may seem on the margins of your FM duties, surveillance cameras and recording devices are nonetheless physical assets that are connected to your building’s infrastructure. Make sure you have a firm handle on this technology.
Rich Cecchini, a storage expert with Seneca, a systems manufacturer, and Jonathan Lewit, senior product manager with Pelco by Schneider Electric, a surveillance solution provider, share their insights on video storage options.
How has video storage for surveillance cameras changed over the last decade?
Cecchini: Video storage started as cassettes with tape selection and long waits to view video sequences. Then we moved to piles of DVDs, which still had similar playback problems. Now we use disk arrays that can hold 1,000 times the capacity of the old options and have instant access to recorded video. Advancements in video storage have also created changes in security video management software. These tools allow network-connected digital cameras to use traditional network infrastructure, which greatly reduces capital and operating expenditures for surveillance.
Lewit: The size of a single hard disk drive (HDD) has increased dramatically, making 4-, 5- and even 6-terabyte drives fairly common these days. A decade ago, an entire digital video recorder (DVR) might approach that kind of data with multiple disks. Now we have the ability to store higher resolution videos at closer to real-time frame rates.
Do storage options differ between camera models, such as analog, PoE, IP, and wireless?
Lewit: From a video management system standpoint, each of these cameras still generates a video signal that can be represented as bits and stored on an HDD. Analog cameras need to be run through an encoder device to translate the continuous waveform into its digital representation. On the wireless side, you may have to take into consideration the bandwidth available for streaming, but once that stream is on the network, it can easily be routed to disks managed by the appropriate network video recorder.
Cecchini: Keep in mind that storing video is completely different than connecting cameras. However, analog cameras generally have lower resolutions and therefore consume less storage space than more modern higher resolution cameras. IP cameras are typically connected via Power over Ethernet or wireless Ethernet, which minimizes the infrastructure needed for a successful deployment.
What kind of storage is available?
Lewit: There are a variety of internal and embedded storage options. Increasingly we are seeing the presence of storage local to the camera, typically in the form of a secure digital (SD) card, although some cameras support connecting to an HDD or solid state drive (SSD).
This enables interesting deployment opportunities where cameras can essentially buffer information at the edge and only transmit high capacity data when requested by the system or client. Alternatively, the onboard storage can also be used as a redundant storage location for data in the event of network or other system storage failure.
Cecchini: Direct attached storage, or DAS, is ideal for inexpensive use of today’s largest disks. DAS drives and enclosures can enjoy the same RAID protection afforded by internal drives and centralized NAS or SAN appliances. DVR and NVR are merely the recorders that storage can be attached to. These can be embedded, internal, or external. NAS and SAN are network-connected storage devices that one or more recorders can use to save and retrieve video.
How does a building owner decide which storage option is the best fit?
Cecchini: There are a number of factors that can be combined for the right solution or become the system’s limitation if they aren’t properly accounted for.
Scalability is the ability to grow or increase capacity. Even the most economic storage solution, DAS, can scale to over 100 terabytes per recorder, but flexibility and sharing are limited when compared to a SAN/NAS centralized storage answer. You also want to increase size conveniently. In this case, it’s preferable to use advanced SAN/NAS storage appliances where space can be more easily increased and even transparently expanded to the recorders.
Storage periods or data retention length affect how much capacity is required. Longer storage periods equal higher video capacity demand. With a DAS solution, a capacity requirement either can or cannot be met. With a SAN/NAS solution, however, you have to look at capacity and scalability. While SAN/NAS capacity is generally much greater than DAS, the appliance must also be able to grow to meet the future size requirements as other recorders are added to the network.
Bandwidth is another consideration. Generally speaking, higher total camera bandwidth generates higher storage requirements. While capacity, storage periods, and scalability are part of the equation, performance has to be considered as well. Bandwidth on the camera side also impacts the server and storage performance requirements. If the storage subsystem is too slow, video frame loss will happen. Even worse, huge chunks of video can be lost and system crashing can occur if the problem is acute.
Where does cost come into play?
Cecchini: Budget is often an overlooked factor and dictated by how scalability, storage periods, and bandwidth are applied. DAS is the most economical solution with excellent performance and fair scalability. But storage is captive to a single recorder, so using more than three recorders becomes inefficient. SAN/NAS solutions show a higher initial cost to implement but show a better ROI as more recorders are added to an installation, though FMs should pay special attention as recorders are added so as not to exceed the SAN/NAS performance capability.
How can facility managers collaborate with their IT department for a successful installation?
Lewit: Facility managers should ensure that they understand the capacities and limitations of their existing network infrastructure. When working with IT departments, clearly identify facility needs and work up plans that appropriately
leverage all the technologies to best fit within their framework.
Cecchini: IT and physical security are increasingly falling under the same roof. Modern IP security solutions are much closer to IT concepts and practices than the older analog television-esque surveillance systems. In almost all cases, an IT/security combination leads to lower implementation and management costs.
But many IT professionals still feel put upon when asked to shoulder some of the security and surveillance burden. After all, their infrastructure was built to IT requirements and budget but now surveillance is asking to use precious resources, particularly network bandwidth and equipment. Many times IT budgets can be expanded to accommodate surveillance requirements or supplemented with security/surveillance budgets. This is optimal but does mean different hardware may be required of IT, as well as additional manpower to manage the security hardware and software.
If budgets can’t be expanded or there is resistance to combining physical security, IT may say surveillance devices can use their wiring infrastructure but not any of their hardware or network. This way, the surveillance group saves time and money by using existing cabling and can use their security specific servers and storage. General computer traffic is then isolated from security feeds, which could pose a virus or malware threat. The standalone security network will also benefit from dedicated bandwidth.
As upgrading storage won’t yield a traditional ROI like other building systems might, what are ways FMs can justify investment costs?
Cecchini: If a surveillance system and storage are meeting a specific fixed requirement, approach it as a traditional capital expenditure. If ROI is important, focus on planning.
Start a security specification covering shared building areas, egress points, exterior areas, and other surveillance areas. Establish camera coverage and storage period requirements. Your future ROI will depend on the scalability and bandwidth allowance made in initial design and small upfront expenditures can pay big dividends down the road.
When purchasing recording servers or storage appliances, do not buy the solution that holds the exact amount of disk drives to meet the present requirement – buy one that has extra disk space or slots to expand. Spending another $1,000 on a larger enclosure will save five to ten times that initial investment down the road. The same applies to the CPU and memory. Upgrading a system for added camera units and bandwidth is much cheaper than purchasing and installing an additional system.
Lewit: As video has evolved, more and more constituents are popping up and video is no longer purely a risk mitigation proposition. Companies want to check in on flow rates to help businesses assess marketing promotions. Supervisors want to validate alarm conditions before heading out in the middle of the night. All of this helps the overall organization be more efficient and connected.
Cecchini: You can also think of security and surveillance as part of your space contract, whether it’s internally or with lessors. Just as lighting coverage is defined, so can security surveillance. Remember that a higher density of cameras drives the storage requirement. Define base surveillance as part of the coverage and then charge for changes and increases to cover costs.