CCTV and BEYOND

The transition from analog to digital video is the next step in the continuum of Security Video Systems (SVS), moving us farther away from a closed-circuit network, but leaving us with essentially the same core problems and an onset of new problems.

Analog video is founded on standards — including Phase Alternating Line (PAL), Sequential Color with Memory (SECAM) and National Television System Committee (NTSC) — developed to provide an interoperable method of producing a video signal. Under this approach, video recorded in PAL (European standard) would be unreadable to U.S-based NTSC standards and vice-versa. Without the proper hardware designed to the correct standard, you would be unable to access video source signals in an analog world.

There are no common and specific standards for the production of digital raw security video. In the case of digital, the raw format of video is supposedly “secret and proprietary.” It is true that digital recorders do export video into a variety of standardized digital formats. However, the raw video signal is proprietary and, therefore, so is the equipment that transmits and displays it.

In other words, the format of high-definition commercial video, (Blu-ray and HD DVD) are also proprietary. Neither of these two competing audio visual products/standards battling for a customer base are interoperable. Similarly, each digital security provider has its own equivalent of an HD or Blu-ray system that, while not necessarily competing, will limit interoperability in the future.

Suppliers of various digital security formats often give an end-user the impression that their systems are more advanced than other systems, which is far from the truth. Most digital recorders export their raw video sources into a recognized common format, such as MPEG, that can be played on a common software program. Other than the exported format, the interoperability among manufacturers that was once afforded by analog systems is no longer available with the advent of digital systems. Many people use the Common Intermediate Format (CIF) to equate quality of video when comparing other video standards such as MPEG. This is not accurate. CIF was developed to standardize a set of video formats used in video conferencing, but is now being applied to digital security recordings. It is currently the closest thing that we have to an apples-to-apples comparison of a manufacturer’s digital recording method.

Digital beginnings — Digital video recorder

The advent of the Digital Video Recorder (DVR) and its quick adoption by the security industry are based on a simple business problem: How does one limit the enormous number of man-hours required to search though linear analog cassette-based video? The solution was developed to enable a video signal to be accessed randomly.

Emerging video technologies enable individual frames of analog video to be captured and transformed into digital frames or pictures, which, like analog video, give the perception of a moving scene. The flexibility of digital video far surpasses the capabilities of analog video. Enhanced functionality such as computer network connectivity, time/date motion detection searching and others were quickly added as a result of this conversion.

Initially, manufacturers that led with this new DVR technology had a majority of the market share since they were the only ones providing this capability. Other manufacturers reacted quickly by developing DVR clones, which were basically home computers. They ran operating systems that had to be upgraded and patched. This is exactly what manufacturers needed: cost-effective computers with the addition of off-the-shelf video capture boards to capture market share. Manufacturers hid behind the veil of proprietary software encoding to differentiate their products. As a result, multiple manufacturers offered their respective DVRs, each with the same shortcomings.

As one can imagine, the DVRs and their Windows operating systems were plagued with difficulties such as the infamous NT-based “Blue Screen of Death,” defragment issues, software instability on the loss of power, and probably the worse of all, the infection by self-propagating “worm” viruses that used these network-attached DVR computers to mount attacks. Lastly, these DVRs were costly, and service was limited because the manufacturers did not truly understand that they were entering a world of Microsoft Certifications, updates and commensurate virus software. Simultaneously, manufacturers dealt with the same problems and answered them in different ways. One notable solution was the emergence of an embedded operating system which, as the term implies, cannot be accessed or written to. The inability to write to the operating system precludes the ability to attach a virus or worm to it. In addition, third-party Microsoft patch upgrades and overall software maintenance are reduced.

Network video recorder

A network video recorder is, essentially, digital transmission from the camera to the recorder. There are two types of basic network video recorder systems, the first being a true digital solution. The camera is connected through a shared network (TCP/IP). Each camera is addressable and routes its video to a common storage medium attached to the network. Unfortunately, this approach causes a number of issues, which include conventional monitoring of cameras and the transition back to the same problems that DVR’s had (viruses, patches).

The second type of NVR system is what may be called a hybrid. This hybrid NVR is no different than a DVR except that the video capture has been segregated from the storage device. The video capture device (encoder) is located in an area where signals from multiple cameras centralize, such as a riser, prior to being transmitted back to its respective head-end system locations. Under this design approach, analog cameras terminate at the encoder, which transmits the video back to the central recording area through a local connection to the network.

Unlike a DVR, both NVR solutions can require a per-camera licensing fee that, depending on the manufacturer, can be a one-time or annual fee. In addition, the NVR is digital, so unless you are going to pay for expensive decoders to transform digital video to analog video, there will be complexities related to monitoring by a traditional CCTV switcher. Lastly, to achieve the same functionality of an analog system, there are a lot of computers. Remember, your network video recorder solution is based on computers managing the system. Therefore, redundancy is a must, and it is not just for computers. The shared network should also have adequate redundancy. Finally, NVR products are fairly proprietary, so camera interoperability is not based on any standard. Therefore, the only way to interface with other competing manufacturing products (cameras) is to hope that an interface exists or, alternatively, to develop an interface using a Software Development Kit (SDK) that can be provided by the NVR or camera manufacturer. On the surface, NVR looks very cost-effective, but can be subject to many “change orders” depending upon the user’s specific needs. Many organizations continue to be challenged by what they have referred to as bait-and-switch tactics when comparing a digital system to the old analog system. In addition, the use of a shared network minimizes accountability by the person installing the digital system. This lack of accountability translates into finger-pointing when dealing with a security systems integrator/end-user or the network administrator/installer.

Common problems

There is one common problem between analog and digital video systems — storage space. The simple question is: How much digital storage can I get on a digital recorder? Formerly, analog video was stored on video cassettes, and depending on the recording rate, it could have been stored for a week or for a day. This was absolute because it was based on the NTSC video standard. There were only a few variables that were affected: the frames captured and the length of the cassette tape.

These variables made it quite easy to give a customer an accurate comparison.

Invariably, the question of storage in our digital era will result in the DVR/NVR manufacturer producing a Microsoft Excel sheet that asks a number of questions and says hypothetically how much video space is available to store. To be fair, unlike analog video where stored video is absolute, digital video is based on frame size and resolution. Also unlike the analog standard, DVR manufacturers use digital images that are primarily stored on hard disks and can be manipulated significantly — from size/resolution, color depth to quality and method of recording. In addition, the changing background or scene will have an impact on the overall file size, which impacts the capability to store video. Finite answers to these questions are elusive. The issue has been — and will be — storage. Once a viable, stable and cost-effective method of mass storage is developed, the possibilities for distributed security cameras will be fully realized.

The digital frontier

Digital technologies mean open networks. Therefore, these networks are susceptible to manipulation. NVRs will use the network to transmit large amounts of data to an ever-growing shared network. Information technology administrators may throttle back security video to prevent network congestion that limits phone or data connectivity (business resources). A shared network is susceptible to multiple points of failure and a host of new attackers that were not previously a problem. The loss of the network means a loss of security connectivity. In addition, the computers that store and manage this video data may invariably be administered by the information technology department. Many IT groups may even charge back operating costs for the maintenance of these computer hardware systems that run software they may not understand.

There are opportunities where NVR technologies make a lot of sense. For instance, remote connectivity is a big benefit of a shared network. It is possible to transmit digital video great distances that previously would have required a hard-line connection at a reduced cost. Schools also could make good use of digital technologies because their networks are traditionally robust. The potential for shared video monitoring to a police cruiser could be beneficial, for example, during a hostage incident. But a shared network could also be accessed by someone other than the police and security. The future of video systems will depend on point-to-point encryption to secure networks where video will be present.

“Putting on my Carnac hat”

Looking into the future, we can see a lot of opportunities for digital technologies, but these products have yet to be fully developed. NVR manufacturers are only now transitioning to embedded operating systems. We are, as we were previously, in a market share battle that has made way for rampant deployment of digital camera/recording technologies. These technologies need to be refined in order to balance the functionality we currently have (with analog) to the new proposed digital technologies. We might see the following occur in the future:

• A standard will be developed to identify “protected” bandwidth requirements on shared networks. In addition, cabling plant standards will clearly identify specific cable coloring and potential port connection for security devices. This will be the result of installation standards or liability.

• Digital storage will increase dramatically and provide a robust platform to allow us to benefit fully from digital camera technologies. There are a number of current storage technology advances that will make this a reality in the next five years.

• Manufacturers of digital security camera systems will leverage this new storage and its benefits. The results of increased storage will have negative impacts on an ever-growing network. The current distribution of digital networks will necessitate separate robust fiber-optic networks specifically for security camera systems.

• Networked video cameras will be standardized. A standard will be developed to allow interoperable plug-and-play communication standards between camera and storage devices. In addition, the need for security will necessitate that encrypted video be sent to a centralized storage device. This encryption will be the result of external/internal threats involving packet sniffing and camera re-routing from shared networks.

• Over a period of years, hardware will be developed specifically for the transmission of network video. More than likely, these new CCTV networks will be fiber-based backbones with Power-over-Ethernet (PoE) connectivity, which will not be connected to a shared network, but rather to a new type of CCTV network that will be digitally based.

With the evolution of the digital cameras, connectivity is increasing, but the catalyst to the revolution of the digital cameras, NVRs and DVRs is rooted in one common theme: storage. Storage has been, and will continue to be, the Achilles’ heel of any security camera system related to connectivity, transmission and retrieval. When we are no longer worried about storage, we will see the full benefits of digital camera systems — far exceeding analog systems. However, those benefits will be at a network bandwidth cost that will necessitate a move back to a closed-network television system — in other words, CCTV.

About the Author

Sean Ahrens, CPP, CSC is a senior security consultant with Schirmer Engineering and has more than 16 years of experience in the security industry, 11 of which has been as a practicing consultant. He volunteers his time on the ASIS International Commercial Real Estate Council (CREC) and previously participated as a founding member of the ASIS Commission on standards and guidelines. He has been responsible for providing security threat and risk analysis, contingency planning, loss prevention and force protection design and planning for private, public, governmental and state organizations. He can be reached at (847) 272-8340 or [email protected].