Disaster Recovery

Surveillance plays critical role in natural and man-made disasters

• By Lee Caswell, Greg Pellegrino
• Feb 01, 2013

Hurricane Sandy disrupted power, Internet, phone and various other technical services for millions of people and businesses along the East Coast in 2012. In the aftermath of the storm, organizations are reviewing the effectiveness—or lack thereof—of disaster recovery plans across all of their systems. Because video recording is increasingly used to monitor and manage the effect of natural disasters, surveillance planners are especially taking care to review internal plans for recovering from disasters, both man-made and natural. The adoption of IP technologies across surveillance cameras, IT networks, edge devices and hardware, such as storage platforms, opens up interesting new options for disaster recovery since video can be stored, copied and moved across local and wide area connections in ways that were simply not available in the days of analog systems.

In the Time of Tapes

When dinosaurs—analog systems and VHS recording—ruled the world, surveillance directors relied on sub-optimal methods for protecting stored video content in the case of a local disaster. Video recording happened in one format—a VHS recorder—and playback was limited to a VHS player running either the primary tape or a subsequently created copy.

With this approach, disaster recovery preparedness often required physically labeling, indexing and transporting bulky, unreliable tapes to a secure offsite location. Creating copies of tapes was a time-consuming task and video was captured and stored at a lower resolution or generational loss made the video suspect as evidentiary material. Even more challenging was the fact that the entire disaster recovery system relied on the delicate process of transporting and locating a single physical tape.

Search capabilities in the analog world were equally limited. Video content on a VHS tape represented a fixed amount of recording time from a specific camera. Content could only be reviewed serially with a limited set of fast-forward and skip options. The process of reviewing disaster footage was cumbersome and required a massive mobilization of staff at the physical tape location, who would methodically plod through the recorded video from start to finish, hoping to find relevant data. For example, following the 2005 London Bombings, more than 400 policemen were marshaled in to review more than 2,500 videotapes.

The Role of Digital Copies in DR

IP video introduced, for the first time, the ability to create identical digital copies of a video clip without any loss in video content. Where tapes introduced generation loss with each new copy, digital systems eliminated this resolution loss by allowing copies to be easily created and stored offsite for recovery purposes. Today, many surveillance departments create copies of locally recorded video on disks, DVDs or USB drives, and then move the physical copy to an offsite facility so that the video is not lost if the primary recording site is compromised.

The simple creation of digital copies can result in some unintended consequences, however. Creating hundreds of DVDs with uncontrolled copy privileges can be like mixing Mentos and Diet Coke, where the results can quickly spray out of control. Multiple copies can quickly increase unnecessary storage costs and be nearly as difficult to track as their VHS counterparts. Uncontrolled copy procedures also present the unwelcome prospect of releasing sensitive video content to the outside world. Ideally, the best practice for DR includes a responsibility to track and control how video copies are created, distributed and accessed.

How WAN Bandwidth Throttles DR Options

The limited availability of wide area network bandwidth forces a conscious examination of why video is being retained, so that the appropriate selection of cameras, image resolution and video retention can be selected. In effect, an optimization puzzle has to be solved for each use case.

For example, a retail store that is sensitive to liability cases may choose to save offsite DR video at lower resolution video over an extended period of time. DR video used to protect critical infrastructure surveillance may require exactly the opposite strategy so that high resolution is kept offsite for a shorter retention time to provide forensic evidence in the case that a threat is carried out at the primary facility. For at least the next five years, the quality of the WAN available to a customer will dictate the video surveillance DR solutions that are possible. Here are three potential solutions.

For several cameras with limited WAN, copy events remotely. IT systems frequently provide DR by copying locally stored data across a WAN to a second and, sometimes, third site. A small network pipe is often sufficient because most IT data changes in small incremental bits each day. For dynamically changing environments, replication over a WAN occurs at night to catch up the remote site when system activity is low.

This “store and forward” DR method is completely unsuited for surveillance environments where a single high-resolution camera can fill a T1 line, in which every single bit of data is new every day and continuous video capture offers no off-duty window to catch up.

Customers also need to remember that typical broadband connections only offer guaranteed download speeds. Upload speeds are carefully monitored, hence the name ADSL or Asynchronous Digital Subscriber Line.

In smaller installations such as retail, banking or remote enterprise environments, there is simply not enough bandwidth available to support any offsite capture of real-time video. For these environments, it makes more sense to simply copy events of interest and send these offsite to be retained in the case anything happens to the primary site.

For multiple cameras with a heavy-duty WAN, dual stream the cameras. Many critical infrastructure projects can justify a high-speed WAN that enables live video to be streamed off-site, as well as locally. In this scenario, incoming video is saved locally at high-resolution quality over the high-speed LAN while a second lower-resolution stream is sent across the WAN to a remote disaster recovery location. This approach matches video resolution to the available bandwidth and optimizes storage costs since the lower resolution off-site copy does not require the same usable capacity.

In some cases, the offsite copies are retained for shorter retention times to further minimize the duplication of storage, servers and licenses. DR site storage costs can also be managed by evaluating which cameras merit a disaster recovery approach since camera views are often not equally critical for forensic purposes.

Multi-streamed camera solutions also are ideal for modern corporate campuses or distributed metro installations where high-speed networks connect distributed buildings or depots together. Video is captured locally onsite and simultaneously streamed to a nearby facility for disaster recovery. This also may be effective for companies that offer more sensitive distributed services, such as daycare or outplacement services.

For few cameras and moderate WAN, direct to the cloud. For sites with limited cameras and moderate WAN bandwidth, the cloud or Video Surveillance as a Service (VSaaS) holds tremendous appeal for customers looking to reduce capital and operating expenses, and for resellers looking to offer a recurring monthly revenue service.

VSaaS can involve video sent to either a public cloud, such as Amazon Web Services (AWS), or to a private cloud. The public cloud offers a lower cost of entry and support but carries the security risks of sharing equipment and access with other customers. Many customers remain concerned that unauthorized access to the public cloud could allow sensitive video content to be distributed or that a hacker could access onsite cameras through the Internet. Private clouds provide enhanced security by dedicating network, storage and server resources to one customer.

For small retail environments, manufacturing sites, restaurants and non-critical infrastructure sites, VSaaS may offer the perfect mix of cost and offsite recovery. For larger critical systems, the bandwidth limitations of the WAN continue to dictate local solutions.

Infrastructure Considerations for Disaster Recovery

Whatever the type of DR site, it is critical to rely on high-availability infrastructure that continues to operate during power, component or system level failures. Pivot3, for example, eliminates any single point of failure throughout the server, network and storage infrastructure so that the system will continue to operate during adverse conditions and will self-heal during component interruptions, such as network or server failures. Disaster recovery is a type of insurance, and for those who anticipate the need to deploy such a system, there is no shortcut for the type of high-availability that Pivot3 offers across all of the key system elements.

For DR systems based on copies of local recording, dual-streaming video to an offsite location, or using VSaaS to private or public clouds, the expectation is that video data is always available. WAN bandwidth may dictate the specific DR solution deployed, but a common decision process on high-availability infrastructure leads users to select systems that have no single points of failure, which offer simple support and seamless expansion without downtime.

Today, surveillance directors experience and benefit from the advantages of IP-based surveillance technology including high-resolution video, remote and on-site video flexibility, remote management and operational efficiency. At the same time, digital video surveillance creates a steadily increasing stream of information, which requires a new approach for both storing video data efficiently and protecting it in case of a disaster.

Whatever the size of your surveillance infrastructure, it is critical to have a DR plan in place to safeguard surveillance operations in the most challenging environments because less than optimal solutions can be costly and a source of failure. Therefore, it is critical to understand DR options for surveillance and which work best for your organization.

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