Caught on Tape, Now Keep it Secure: LTO Technology and Video Surveillance Benefits and Best Practices
The video surveillance industry has evolved dramatically over the last 50 years. From
the days of whirring VCRs, where individuals were literally, “caught on [VHS] tape”, to
the introduction of digital video recorders and spinning hard disks – and now, an era of
network-based video surveillance and associated IT infrastructure. During this transition, the
hard disk drive displaced VHS tape as the typical media for storing video surveillance footage.
However, with the number of higher megapixel cameras on the rise and longer retention
requirements end-users are struggling to deal with the data and cost requirements associated
with storing this amount of footage. In systems with long-term data retention, end-users can
now use file-based tape storage such as LTO (Linear Tape Open) technology in combination
with disk, to effectively meet their requirements in a cost effective manner without
compromising on the quality of the video stored or the length of time the video footage
is retained.
The Three main drivers of greater video surveillance storage requirements:
- Greater numbers of cameras
- higher specification of cameras
- Increased value of data & longer retention times
Greater number of Video Surveillance Cameras
The number of video surveillance cameras sold globally in the last decade has
increased year-on-year. In the 2017 calendar year, the market forecasts there will be over 127 million
video surveillance cameras sold via professional channels. 98 Million
network surveillance cameras will be shipped globally through professional sales
channels, almost 29 million HD CCTV surveillance cmaeras will be shipped
globablly through professional sales channels and 400,000 body worn cameras will
be shipped to law enforcement agencies globablly.
Several overall factors are driving the demand for cameras:
- Increased awareness of the technology
- Security climate
- Legislation
- Multiple uses
- Price decreases
Higher Specification of Cameras
One of the most important requirements of a video surveillance camera is be able to
automatically adapt to changing environmental conditions and produce consistently usable
images. Image quality is complex with many different components. Several of the components
of a better quality image can be measured through the camera’s specifications.
The market has
measured an uplift in the specification of cameras across several different parameters.Resolution: Currently the most common network camera
shipping is 1080p resolution but there will be continued growth in shipments of higher
resolution cameras. Four megapixel cameras are increasing in popularity and with vendors
marketing 4K resolution cameras for wide area surveillance even higher resolution cameras
are expected to gain market share. Equivalent 4K resolution video is four times the file size
of 1080p.
Currently of the 98 million network surveillance cameras shipped globally, 3%
will be 4K resolution or above. In 2020, 29% of network surveillance
cameras shipped are forecast to be 4k resolution or above.
Increased Value of Data & Longer Retention Times
The vast majority of recorded video surveillance footage is never reviewed. As much detail as
possible should be retained until it can be determined which parts are relevant or valuable. For
security purposes the value usually relates to the recording of a security incident. However,
the uncertainty of which parts of recorded video are going to be useful often means trade-offs
between the quality at which video is stored and the length of time it is stored.
LTO Technology and Video Surveillance - LTO and LTFS
Linear tape open (LTO) technology is an open format of magnetic tape data storage jointly
developed by HPE, IBM and Quantum.
In the non-video surveillance wider IT market, LTO
technology is primarily used for data back-up, disaster recovery and long term data retention.
It is often used for making multiple copies of data and for cold storage offsite in vaults. Since
the 2010 release of the fifth generation, LTO technology has included the linear tape file
system (LTFS). LTFS utilizes partitioning to create an index which points to the requested
file positions on the tape. This means that data can be dragged-and-dropped and viewed in a
similar way to hard disk drives.
The LTFS format provides a self-describing cartridge which means applications do not require
any additional information to read the data stored. In the event of a disaster where loss of data
occurs, data can be recovered from tape.
In a tape library configuration used for long-term retention the time to locate and start reading
data is slower than a disk array. However, this is offset by the potential to offer tape as a lower-
cost, high-capacity alternative to hard disk drive arrays for longer term retention. Tape does
not substitute disk as primary storage.
The LTO format has a published technology roadmap with future specifications.
What the LTO technology roadmap means in terms of video surveillance storage.
- LTO-7 (6TB RAW)
- 13 Days x10 1080p or 7 Days x5 4k streams stored per cartridge
- LTO-8 (12.8TB RAW)
- 29 Days x10 1080p or 14 Days x5 4k streams stored per cartridge
- LTO-9 (26TB RAW)
- 58 Days x10 1080p or 29 Days x5 4k streams stored per cartridge
- LTO-10 (48TB RAW)
- 107 Days x10 1080p or 54 Days x5 4k streams stored per cartridge
What can LTO Technology offer the Video Surveillance user?
When utilized in a multi-tiered storage solution, an LTO tape library can be implemented as a
cost effective, connected, long-term, high-capacity storage tier. End-users can manage their
storage system and remain within budget as tape can provide a larger capacity storage tier and
longer term retention for the same cost. This means end-users can compromise less on video
quality and retention time by using tape. Every detail can be stored until users can determine
later what should be kept.
The utilization of tape to store video will not be best suited for all video surveillance applications.
Multi-tiered storage works well with a high number of camera feeds which require extended
storage retention at maximum quality. Data is transferred automatically between storage
tiers based on pre-defined policies. The capacity of each tier and policy governing data transfer
between them is typically based on the likelihood of requiring the highest performance. For
example, the most recent video may be kept on the highest performing disk tiers in the initial
7-14 days post-recording when access is most likely to be required. After this, it is moved to a
tape tier (at which point it is deemed unlikely to be required for review). However, the key
point about this configuration is that data remains available through the VMS should review
be required. In addition, any video flagged up in a security or operational event of interest may
have a different policy and may be retained for longer. Where events are required to be kept
long term or video evidence is used, a copy may be automatically transferred to a particular
tier or even duplicated to offsite storage.
Using tape in a multi-tiered storage solution for long-term retention can mean that rather
than pushing data to the cloud for storage, users can retain full ownership and access to their
data for minimal cost. Cloud storage can be used as an effective storage tier, particularly in
collating data from small camera count multiple site installations, or as an offsite backup of a
small amount of mission critical camera feeds. However, as a storage tier for high capacities
or long-term retention, often there are additional costs to cloud storage which reduce its
viability. For example, high bandwidth costs, access and retrieval charges. Chain of custody is
also a key concern as there are often significant premiums beyond a list price for the use of a
government (for example CJIS) certified secure data center.
Total cost of ownership (TCO) analysis should be used in conjunction with performance
analysis to make a purchase decision for storage. A balance between cost and performance
is often necessary. In many scenarios the speed of data recall offered by a tape library is not
sufficient and it should be discounted. Yet, for some users if they can trade off immediate,
for near immediate access speeds to their oldest data, tape can bring high capacity, long-term
retention storage at price points they would otherwise have been unable to afford. Once the
disk tier is configured further disk storage may only be required if additional bandwidth or
camera streams are added. When only increasing the length of time data is retained building
out capacity on tape can become even more economical as capacities scale.
In one example of a TCO analysis, when maintaining a storage system over a decade the
comparison between a LTO tape library, an all-disk and a disk-cloud hybrid solutions found
that the TCO for the LTO library solution was nearly seven times lower than the all disk
solution and over five times lower than a disk-cloud hybrid solution.
As an approximate cost comparison of individual media, a recent LTO technology cost audit
found an average retail price of $0.02/GB RAW, for a LTO generation 7 cartridge.
The
HDD market tracker estimates a typical enterprise grade HDD price at $0.06/GB.
Conclusion
The evolution of the video surveillance industry is causing a video surveillance data explosion.
The multiple uses of cameras and lower prices mean there are now a greater number of video
surveillance cameras entering the market than ever before. The greater number of cameras
and higher specification new models are producing increasing amounts of data. The length
of time this data is being retained for is also increasing. These factors have placed greater
demands on storage systems and on budgets to be capable of securely retaining large amounts
of video surveillance data for extended periods.
The requirements of certain video surveillance environments for high capacity, long-term
retention with infrequent recall of older footage mean file-based tape such as LTO technology
paired with disk storage can provide an excellent value proposition as a video surveillance
storage solution. LTO technology can offer users full access and control over their data with
long-term retention and high reliability whilst keeping costs to a minimum. LTFS and the
batch pre-fetch plugins, available for many leading VMS solutions, enable end-users to simply
go back in time further within their preferred video management application, gaining valuable
insights which may otherwise have been lost due to compromises on stored video quality or
retention times.
Contact your BackupWorks.com account rep today at
866 801 2944 and find out more about LTO Tape Technology with LTFS and Video
Surveillance.