Terabytes, petabytes, exabytes, zettabytes, brontobytes...what’s our security world coming to?
When you combine the trends of more surveillance cameras, higher bandwidth requirements, fatter bandwidth pipes and the continuing decline in storage costs, you get near-exponential growth in bytes stored. The question is, how do we manage this vast amount of video data? I’ve discussed this question with several large-scale storage vendors recently and learned some very interesting things.
First, there are well-developed content management systems available; however, managing “regular” data is different from managing video data — particularly streaming surveillance video. Whereas enterprise data consists mainly of small random blocks that are primarily reads rather than writes, video data are large blocks of data that are written far more than they are read. Further, you must organize the files and handle Metadata (tags) that go beyond date and time — a task that VMS and video storage vendors deal with on a regular basis.
This helps explain why those that can tag — such as analytics providers, and high volume storage providers — regularly seek to partner with VMS suppliers, who are the gateway between users and the external storage connected to the network (NAS, DAS, SAN). Innovation and implementation success occurs around these relationships. The manner in which the information is marked, cataloged, and shipped off to storage will directly affect the ease and speed of pulling it back out for review.
Companies providing storage solutions are ready. Pivot3, a familiar face in the industry, offers a purpose-built platform that integrates server virtualization technology from VMware to minimize or eliminate the need to provision, power and maintain dedicated storage servers. Their environment consists of 3-12 appliances, each with its own operating system and capable of running a virtual server infrastructure, hosting a VMS. The operating system is designed to handle large blocks of compressed video and the inevitable bandwidth spikes that occur when, for example, a scene becomes rich with motion or, perhaps, where the lighting is inadequate for the camera. It can scale to 432 TB, but it also capable of integrating with existing NVRs and DVRs.
NetApp, the second-largest storage provider and vendor to major data centers, has packaged raw storage horsepower into a small footprint: 180 TB in a 4 RU space (60 drives), scalable to 1080TB. The system’s read/write speeds are impressive — 4.4 GB/sec for Read, 2.4 GB/sec for Write per 4 RU unit. Video applications and control reside elsewhere. This is sheer storage and lots of it, efficiently packaged to limit space requirements in control rooms or data centers.
Most video is stored for a limited period (usually less than 30 days). It could be the user’s situation or needs do not demand anything longer, but the decision may also be driven by storage costs. In a prior product generation, the digital tape “jukebox” was an answer to long-term archival — now, tape may be back.
New entrants to the industry, such as Crossroads Systems, working with tape library provider Spectra Logic, promote a technology based on LTFS (Linear Tape File System) to create a storage center that sits on the network, looks like a network device, holds a ton of video, and costs about 80 percent less than hard drives, with better reliability, higher density, and less energy consumed. Tape capacity is similar to SATA drives, 1.5 or 2.5 TB.
The catch is lower read-write speed (transfer rate of 160-600 MB/sec), which Crossroads achieved by front-ending the tape with a StrongBox (server with HDD storage) that’s a cache to manage tape storage and speed information retrieval. Read-write capability is more limited than pure HDD systems, but it may be a good solution for long-term archival.
When provisioning storage, take a long look at Total Cost of Ownership (TCO), as well as performance and redundancy. Consider not only acquisition costs, but electrical usage, heat generation, space requirements and expandability.