Cool Memories? Hot Storage!
When it comes to security video, memory lane started with a videocassette. Today, tried and true storage comes in myriad shapes and sizes.
Choice, however, comes with challenges. As an enterprise security leader, what do you need to store today, how can storage scale up when needed, what’s the total cost of ownership, how can storage handle video streaming from higher resolution cameras and the needs of retrieval for forensics and business uses? Then there is the question of security of the stored video, especially when it comes to hosted storage, regulations, requirements and privacy issues.
But, if you think that storage is getting a lot cheaper, thing again. For example, if the cost of a terabyte of hard drive storage is about $150 for a SATA (serial advanced technology attachment) drive, that doesn’t include the cost of the power supplies, boxes and racks to mount the drives. So the cost for the drives only in an example for, say, 20 cameras is $23,400, plus the accessories. The result is that the average market price per terabyte for video surveillance storage is between $750 and $2,000, depending on the source. But don’t forget the cost of the AC power to spin the drives and the estimated cost to cool the drives so they function properly. It’s estimated that for every $1 spent to power computer devices (such as hard drives), it costs another $1 to run and cool them.
Security of Storage
And if the recorded video is so important to store, then it must be backed up. The bottom line: The cost of security video storage can be higher than the wholesale cost of the cameras themselves.
It all adds up.
For instance, located between the Bellagio and Monte Carlo Resorts on the Strip, the new CityCenter is big, even by Las Vegas standards. It includes the 61-story, 4,004-room ARIA Resort & Casino. And to help ensure the safety and security of the site, North American Video (NAV) designed, built and implemented an enterprise-wide video surveillance system. At its heart, the custom hybrid solution centers on a Honeywell video management system and features multiple matrix systems spread across seven different head-end locations. There are more than 3,700 video surveillance cameras, all being recorded.
DVR and NVR Solutions
Digital video recorders (DVRs) continue to be storage workhorses. Integrators and some end users still prefer to use DVRs. They’re economical and provide simplified installation, and they’re well-suited to certain applications, especially those that involve confined locations, each with a handful of cameras. Hybrid DVRs allow users to record and playback older analog and newer networked camera input. The units have a smaller form factor, consuming less space, so that some can be mounted on the backs of LCD monitors or in structured wiring cans for covert applications.
Until IP dominates video systems, both DVRs and network video recorders (NVRs) can be considered a good investment. But clearly IP-based networked systems using NVRs are the future, but analog systems using DVRs still represent the bulk of installed systems, thanks to megapixel imaging and H.264 compression as two important trends.
When it comes to tried and true storage, compression technology hits three milestones: reduced bit rates, bandwidth requirements and storage costs. But, with the appeal of megapixel and high definition cameras, DVRs and even NVRs can be pushed to the max.
No doubt, capacities of network-attached storage and external hard drives have risen and costs have fallen. And, when it comes to bandwidth, most network managers use software to manage their bandwidth. Additionally, multi-streaming is available in most DVRs. This allows the DVR to store video on-board in high definition and transmit at a lower resolution to conserve bandwidth.
In a networked world, there are numerous options.
A storage area network (SAN) is a storage device such as disk arrays accessible to servers so the devices appear as locally attached to the operating system. A SAN typically has its own network of storage devices that are generally not accessible through the regular network by regular devices.
Moving to Arrays
File-based solutions include network attached storage (NAS), devices that are gaining popularity. Potential benefits of network attached storage, compared to file servers, include faster data access, easier administration, and simple configuration, often arranged into logical, redundant storage containers or RAID arrays. RAID, redundant array of independent disks, provides increased storage functions and reliability through redundancy.
Then there is virtual storage. Storage virtualization includes concepts as a tool to enable better functionality and more advanced features within the storage system. Broadly speaking, a “storage system” is also known as a storage array or disk array. In these designs, IT works with security to estimate surveillance image needs but does not necessarily set specific hardware to handle it. Storage locations move around as streams come in and storage increases or decreases.
Then there is cloud storage, where security video is stored on multiple virtual servers, generally hosted by third parties, rather than being hosted on dedicated servers. Hosting companies operate large data centers; and people who require their data to be hosted buy or lease storage capacity from them and use it for their storage needs. The data center operators, in the background, virtualize the resources according to the requirements of the customer and expose them as storage pools, which the customers can use themselves. Physically, the resource may span across multiple servers. Cloud storage services may be accessed through a Web service application programming interface or through a Web-based user interface.
Hosted Storage Services
Hosted video services can include storage. Earlier this year, for example, ADT Commercial introduced a hosted video recording and management system centrally managed and aimed at retailers. Using an Internet connection and IP cameras, these enterprise security leaders can access their video remotely from anywhere. ADT handles system maintenance as well as storage of recorded video.
There is also memory at the edge. For some applications, storage in the camera makes sense. Bandwidth may be getting cheaper on local area networks, but the problem with video across networks can get trickier. More network cameras are being added, with a growing demand for higher resolution and faster frame rates, and the increasing need to access the video across wide-area networks, the Internet and wireless networks. However, when you store video right in the camera, no bandwidth is needed for recording. Another benefit impacting bandwidth: When video is recorded in the camera, you don’t need to stream the video; you can send it as a clip. This makes a big difference.
When it comes to storage, security video data is different than other IT storage. The amount of data coming from the cameras is huge and continuous. The workload is constant, i.e. the rate of writing data to the disk is constantly high, not in bursts as with typical IT applications.
With this in mind, welcome to yet another buzz word: ingress, as in ingress of streaming video. Storage devices need to be able to accept incoming video.
When it comes to terabytes and RAID, the Dallastown Area School District in Pennsylvania upgraded its video surveillance technology from a small system of analog cameras recorded on video cassette recorders to an end-to-end IP video system from Bosch Security Systems that provides surveillance of the area’s high school and middle school.
A Separate Infrastructure
Using extra fiber wiring leftover from a previous networking project, the IT department, with the help of a network infrastructure value added reseller, created a separate security network for the video surveillance system. Using a separate network helped to eliminate any concerns over sharing bandwidth with existing network traffic.
The cameras’ Web servers are password protected, enabling the IT department to control access to the cameras and give users varying levels of permissions to administer the system or change settings. This was an important feature for the IT department, as all other IT products used in the school system have this capability, and they have come to expect it from their vendors.
For recording, video is sent across the district’s security IP network for storage on five RAID arrays, holding 14 terabytes of data. The cameras can stream directly to the SAN through an IP-based storage networking standard called Internet Small Computer System Interface (iSCSI).
The IT department chose to use an iSCSI SAN for video recording because they were already familiar with this technology as it is used for network storage of other district data.