Technology Game-Changer

Linear tape file system revolutionizes video surveillance storage

• By Paul Leury
• May 01, 2013

According to IBM, 2.5 quintillion new bytes of information are created each day—that’s 1 with 18 trailing zeros. The explosion of “Big Data” has touched every industry. Video surveillance is no exception.

With regulatory retention demands on the rise, especially for security data, the dollar-per-gigabyte equation becomes more important than ever before. New linear tape file system (LTFS) technology ensures data preservation and enhances data mobility, offering comprehensive accessibility and security. There have been advances in tape that help tackle this cost-capacity challenge and keep all data rapidly accessible, without devouring a budget.

When a security incident occurs, surveillance footage is often needed without delay. When data is the cornerstone for resolving a safety issue, difficulty retrieving critical data could have detrimental effects. Budget constraints, higher-quality imaging demands, and state/federal regulatory-compliance standards drive the need for low-cost digital storage for video surveillance data.

Facing the Challenges

A traditional CCTV–based surveillance system comes with challenges of low-image quality and limited access. Moving to a digital IP video surveillance solution brings benefits of scalability, high-quality imaging, high availability and more centralized management, but many facilities have been reluctant to change because of the associated costs of storage and bandwidth constraints. Due to higher resolutions and better image quality, file sizes are continuously growing to accommodate more pixels and image detail.

A good deal of the cost—as much as 50 percent in some cases— is due to the additional data storage capacity needed to support the upgraded systems. Additionally, higher-quality imaging delivered by IP cameras is becoming essential for facilities, such as correctional facilities that are required to meet video-quality compliance standards. Longer video-retention times come into play as well, with video evidence becoming increasingly important in criminal convictions and protection against false insurance claims.

When considering how to manage surveillance data, a management software platform is key. Beyond the management, however, a secure-storage platform should be employed to guarantee the safety, reliability and accessibility to the data.

While HDD and high-performance SANs are typical for active data storage, they can become quite expensive and cannot cost-effectively keep up with the growing storage demands. Surveillance streams may be coming from hundreds of cameras and require high-performance applications or media while the data is streamed from the camera to an encoder or networking switch, and finally to the centralized control location. In recent years, this scenario has resulted in a need for an expansive SATA or SAS disk system.

Re-emergence of Tape

With their scale-out, energy-hungry systems, it’s no wonder that storage can account for more than 50 percent of today’s surveillance system costs. But new tape-based technology is quickly giving security managers hope for more reliable data access and drastic cost reduction.

Tape has recently re-emerged as a renewed and more powerful medium for surveillance data. But, tape is slow, unorganized and difficult to access, one might have heard in the past. While archaic tape systems certainly came with their fair share of lamentations, the game-changing LTFS technology has reinvigorated tape as an easy-to-use, file-based system for high-volume data storage. It’s turned out to be quite the appealing option for organizations that depend on large-scale surveillance systems.

Developed by IBM, LTFS refers to the non-proprietary form and organization of data on LTO (linear tape open) media. LTFS is a way of organizing data on tape that simplifies rapid file access while protecting tape from vendor lock-down. In other words, no specific vendor solution is needed to read data that is stored on LTFS. The standard empowers tape as a file-based storage medium without attaching metadata or making modifications to files.

The LTFS software can be downloaded from any major tape vendor’s Web site and applied to LTO-5 and LTO-6 tape cartridges and drives. Essentially, LTFS partitions a tape into an index (partition 0) and a general data area (partition 1). As data is written to a tape, the index retains enough metadata to know exactly where on a tape a file resides. The benefit is two-fold: Tape data can be more efficiently retrieved because an application will not have to read the entire span of the tape to locate a file, and tape is now empowered as a file system and can interface with other file-based applications and software. For the video surveillance world, this means that once inflexible, offline tape is now a living part of file-based feeds and surveillance data management.

Tape can now serve as network-attached storage (NAS) because a tape library can connect and interact with file-based applications. The tape-as-NAS solution is especially compelling because it allows a file-system view of tape data from applications that are familiar to end users. Accessing files from the archive can be accomplished via simple point and click from the application. The ease at which this allows users to locate specific surveillance footage is unmatched.

Vendor Neutral and Cost Effective

LTFS was created to solve the challenge of vendor lock-down on tape data. Because LTFS is open-standard, it ensures that LTO- 5—and LTO-6, when shipped—can be read by any LTFS-enabled device, regardless of vendor. LTFS/LTO media can be purchased from any major tape media vendor and read by another vendor’s LTFS drive. Thus, data isn’t restricted or in danger of becoming inaccessible because one vendor’s technology becomes obsolete or unavailable. By allowing integrators to build surveillance solutions without worrying if the underlying tape storage layer will be compatible down the road, a great sense of peace of mind and assured accessibility is gained.

According to a report authored by The Clipper Group last year, the operational costs associated with disk-based surveillance video storage can amount to more than 15 times that of tape-based storage. Disk requires constant energy for spinning, cooling and operational tasks. On the other hand, an LTFS tape library keeps energy needs to a minimum, helping to create a more sustainable datacenter. Additionally, tape is much more reliable than disk. LTO boasts a best bit-error rate of 1 x 10e17 (that’s about one bit error every 12 petabytes). Organizations can buy a 1.5 terabyte LTO-5 cartridge for about $35.

In one study, an analyst found that switching from a SAN disk solution to an LTFS-based storage system resulted in an 80 percent reduction in the total cost of ownership for storing data. It’s noteworthy to add that the study was conducted over a 10-year period using 1 PB (dual copy) of video data.

Faster Access

As mentioned previously, security data is often needed under tight time constraints. LTFS makes it simpler and faster to pinpoint specific files stored on an LTO tape. Because LTFS is a selfdescribing file system, contents are categorized with the index stored in the first partition of the media.

Data written on LTFS media can be used for a variety of applications. Surveillance footage can be shared between different entities as needed. Tapes from an LTFS library can be exported and read by any other machine. This allows surveillance professionals to deliver content as requested or mandated by authorities or other organizations. It also allows separate groups to more instantly access and share the video footage, increasing the usefulness of the surveillance system when needed most.

Data storage is fundamental. Accessibility, performance and cost-savings are what make one type of storage stand apart from alternatives. While organizations will certainly continue to employ disk, SAS or SATA for high-availability surveillance data, advances in LTFS and LTO tape media are beginning to make an impact in overall surveillance storage infrastructure designs, not to mention budgets. LTFS delivers a solution for surveillance footage that needs to be retained cost-effectively. To cope with rapidly growing data volumes, the surveillance industry can look to tape and LTFS as a possible solution for large-volume data storage and savings.

This article originally appeared in the May 2013 issue of Security Today.