March 14, 2012
Today's video surveillance industry is in the middle of a paradigm shift. With the increasing popularity of Internet Protocol (IP) cameras, it is believed that the market is shifting rapidly from analog to IP video surveillance technology. This transition is spawning rapid innovations to increase the capabilities of video surveillance systems. One such example is the advent of NVRs offering a choice between standalone units or recorders as part of a PC assembly .This development in the NVR poses the question: should clients opt for an NVR that is PC-based or a self-contained, embedded unit which only requires attachment to an Ethernet-ready interface?
This white paper will maintain that video surveillance users who opt for an NVR using an embedded, dedicated Linux operating system within a self-contained unit will benefit from performance which is superior to that offered by a PC-based NVR in terms of ease of use, system stability and decoding capability.
Functions common to the two approaches
Before distinguishing between the two video recording solutions in the surveillance market, it will be useful to list the core functions that are common to both approaches. These include: recording; archiving; display; playback; search on parameters such as date, timeline and event; camera management; triggered recording on prescribed events and export to removable media. NVRs are also usually expected to be able to handle VoIP packets. Once digitalized video has been streamed, end-users expect to be able to treat it like any other network data, viewing it locally, on LANs and remotely from web browsers. They also expect to be able to exercise PTZ control over cameras remotely, configure settings and even perform upgrades remotely.
Comparison of embedded network video recorders (NVRs) with PC-based NVRs
Embedded NVRs are distinguished from PC-based NVRs primarily on how they operate and the features they provide. The stand-alone NVR comes in a single, compact enclosure. By contrast, a PC-based NVR is a peripheral addition to a system involving a CPU, keyboard and monitor. In confined locations, an embedded unit performs a similar if not wider range of functions while occupying less space. Embedded NVRs have overcome their perceived shortcomings in terms of storage capacity and types of storage medium through use of devices including IP-SAN, eSATA, NAS (network-attached storage) and Fire wire. Furthermore, embedded NVRs can support interfaces to other surveillance devices which can be conveniently integrated with alarm systems and access control systems as well as PTZ remote control systems.
Unlike a PC-based unit which is likely to run a range of Windows™ applications, an embedded NVR benefits from the stability that comes with Linux code which is optimized to run only applications relevant to the surveillance tasks required. An embedded operating system contains only the software components necessary for the specific functions of the NVR, and the unit will be supplied with optimum configurations straight from the factory after rigorous testing.
The precise architecture of the embedded NVR units makes them less prone to crash. However, the PC methodology for NVRs is certainly 'open' in terms of the addition of external storage, installation of software etc. The controls are embedded into the NVR; they are an integral part of the panel rather than an adjunct, and the activity of operators can therefore be more easily restricted to legitimate usage.
Beware of the curious security guard - This scenario is exaggerated but only slightly. Find an integrator or end-user that is willing to be honest with you and they may well describe situations such as the following. It is all too common for a bored security guard who sees a Windows™ logo on a PC screen that he is monitoring to think: "I know this environment. I play games on it at home. I could play Solitaire on this and if I just uninstalled that program I would release enough room to install 'Battlefield 2.' And I guess I could plug my USB-driven phone into that port over there." Cases of a staff member plugging a phone into a surveillance installation and taking out a whole security system are common. No amount of foresight can anticipate unpredictable behavior by junior staff. But the contrast with an embedded NVR is obvious. There is little scope for attaching foreign devices to the panel and any such device will not be recognized by the NVR.
Embedded NVRs consistently outperform PC-based solutions in their ability not only to perform complex decoding but also to give the user reliable video playback and preview. Currently, certain NVRs are among the few units which can perform both local decoding and playback, with decoding of up to 16 channels at 1080p being achievable. The processing demands made on a PC-based solution to achieve comparable performance are far higher than those required of an embedded device, and necessitate powerful, expensive CPUs.
Ease of Use
Embedded NVRs can have operating panels based on the very best intuitive design principles. LED signals, digital inputs and outputs, push buttons and dials can all be arranged in an ergonomic way. Sensible layout in a panel approach rather than a screen-based GUI can replicate the ease of use found in a PC but without the vulnerabilities described above.
Power consumption and manufacturing carbon footprint
Embedded technologies are helping the surveillance industry to go green in marked contrast with the PC approach. The power consumption of an embedded NVR is approximately 70W which is less than an incandescent light bulb. By contrast, the likely power consumption of a PC capable of running an NVR is approximately 250 watts and together with a large enterprise-grade monitor, the total figure will be about 350 watts. For any end-user mindful of their carbon footprint, these figures alone must do much to settle the debate.
Default option rather than a decision based on comparative analysis
NVRs have been a mainstream offering for three years and it is likely that the embedded approach will soon take precedence over solutions using PCs. Nevertheless, a PC-based NVR will still have its own stage as an additional approach to the embedded method. The benefits an embedded NVR offers – reliability, stability, ease of use and more –allow enterprises to maximize the value of what they already own. Moreover, with all the components embedded into one box, it occupies small space and can be perfectly disguised in any location. This makes the embedded approach more suitable to be installed to any spot even hard-to-reach location, prohibiting the unauthorized staff or intruders to access to sensitive video footage. For end-users who have not yet implemented an NVR, the discussion in this white paper should make a convincing case that the embedded NVR approach must be the preferred option rather than a PC-based NVR. Any considered evaluation of recent product progression will lead to the conclusion that the embedded NVR has already become the default option.