The Power of PoE

Convergence faces the challenges of infrastructure and flexibility

  • By Koen Geirnaert
  • Apr 01, 2008

With an explosive demand for security monitoring worldwide, cameras are appearing in every conceivable location. The challenge is how to support this rapidly growing infrastructure with affordable and flexible real-world solutions. The adoption of PoE offers new opportunities for the design of products directly powered over Ethernet lines, drastically reducing overall installation and maintenance costs.

In the video surveillance market, the days of analog CCTV cameras are numbered. The IP camera is encroaching on the analog camera's domain while security awareness is boosting the installed base of cameras. In addition to cameras, the market for access systems, RFID tracking, biometric identification, fire detectors and other security equipment continues to expand. Some of these systems require high-bandwidth networks to operate. Due to the widespread availability of IP networks, Ethernet is poised to become the dominant network for security systems. As more devices are connected over Ethernet, the momentum continues to build toward virtually everything being interconnected.

The Convergence Trend
In the security industry, like many other industries, IP convergence is a key driver. The convergence of all security equipment on the same network has many advantages. Security equipment can be accessed from anywhere via the Web. The security network benefits from technology such as firewalls and secure connectivity software with encryption. Total cost of ownership for the security network infrastructure is lower with off-the-shelf interfaces and switches. Installation flexibility is increased thanks to adding, moving or removing equipment to plug-and-play; therefore the system configuration can be modified quickly, allowing system enhancements and incremental capital investments. Building security networks and enterprise data networks are starting to converge.

Another important trend in the security world is integration. Numerous features and capabilities are being added to security systems. In recent years, security cameras profited from numerous technology advances. Today, CMOS image sensors lead to improved image quality and higher frame rates. Network and media processors enable the handling of captured image data and organize them into IP packets. PoE was introduced on the box camera. Tracking capabilities were implemented via onboard stepper motors. Now, the camera market is ready to add even more features, such as speakers, microphones, sensors, door-lock interfaces and fire detectors. The camera is evolving into a comprehensive integrated security tool.

PoE has taken off in the security camera market. Today, a significant share of box cameras have a PoE-powered device on board. PoE is well positioned to bring additional power to enable the convergence and integration trends in the security market.

An Evolving Standard
Initially, the IEEE802.3af PoE standard supported the modest power needs of devices such as VoIP phones, wireless LAN access points and even box cameras. But the standard is evolving to the higher-powered IEEE802.3at, also called PoE+. This standard supports delivery of even higher power levels, which in turn serves the convergence principle. With PoE+, most types of cameras can be connected at virtually any point on the network. No power plugs need to be provided, additional wiring can be avoided and repositioning is plug-and-play. Power supply backup via an uninterruptible power supply on the Ethernet switch is easy to implement with PoE-enabled systems.

In the market today, PoE convergence has encompassed the box camera as long as power consumption is within the 13-watt power budget of the IEEE802.3af standard. With the development of the IEEE802.3at PoE+ standard and its 30-watt capability, the security market will be able to include PTZ and dome cameras in the power budget.

The desire to integrate more capabilities on the camera platform also is driving power requirements. Speakers, heaters that prevent moisture build-up and door-lock supplies are particularly power-hungry features. As the advantages of UPS backup become more obvious, even more external features will be attracted to the camera platform. Furthermore, everything still needs to fit in the same box. Silicon integration of different devices on the camera platform is adding value.

What are the latest decisions in the IEEE802.3at standard committee and how can powered device circuits support these higher-power requirements? The .at standard is targeted to deliver up to 30 watts to the load. This is accomplished by raising the minimum voltage on the cable from 44 volts for the .af standard to 50 volts for the .at standard. A Cat 5e/6 cable is proposed for higher power because of lower resistance.

The power level in IEEE802.3at is raised from 13 watts to 30 watts by changing the maximum cable current from 350 mA to 720 mA. Note, however, that the 30-watt power budget is not fully available for the powered device, as a fraction of the sourced power is dissipated between an Ethernet input jack and the voltage regulator output.

The losses are spread over the path between the input diodes, the powered device pass switch and DC/DC converter. The overall efficiency between input and output will be in the range of 85 percent, resulting in a maximum power budget for the application of 25 watts for IEEE802.3at and 11 watts for a .af setup.

However, as there are already some .af-compliant products available in the field, how will the new “.at” standard be seamlessly deployed? The two classifications considered by the IEEE standard will enable higher-power equipment deployments. In the first method, the reserved Class 4 handshake is applied two times. This is the so-called Layer 1 handshaking and is implemented in the hardware of PSE and powered devices. Interest in the Layer 1 approach is mainly driven by the need for basic midspan equipment, where it is desirable to avoid having to access the data channel stream.

A second method is to apply the reserved Class 4 handshake on the powered device, start up under low-power conditions and communicate via the data channel between the application and the switch that more power is required. This method is called Layer 2 handshaking.

The highly integrated high-powered device, with high-power capability beyond 1 amp, combines in a single unit a high-power, PoE-powered device hot-swap pass-switch and a highly efficient DC/DC converter. The PoE-powered device is fully compliant with the IEEE 802.3af standard and supports Layer 2 handshaking of the 802.3at specifications. Highly integrated solutions, such as this, lead to a reduced bill of material and contribute to size reduction of the complete system.

In this application, the output voltage is applied to serve several parts of the camera. For example, on a PTZ camera platform, there are not only the image sensor and media processor, but also the stepper motor drivers for controlling the axes movement. The stepper motor drivers consume a significant amount of the power budget and, therefore, the IEEE802.3at standard enables PoE+ for these platforms.

The story is broader—heating systems or fans onboard with the camera to remove moisture are power hungry. Outside the camera world, other devices such as MIMO wireless LAN access points and RFID access points need more power than 13 watts to operate. Therefore, the IEEE802.3at standard is an enabler for further convergence of power distribution over Ethernet.

PoE is well positioned to serve the IP convergence and integration trends in the security and security camera market. Now, PoE+ is emerging to meet the power requirements of a broader range of security applications. Some PoE-powered devices already provide full solutions compliant with the latest developments of the IEEE standardization activities. This is expected to dramatically accelerate the wide deployment of this new class of products.

Featured

  • The Evolution of IP Camera Intelligence

    As the 30th anniversary of the IP camera approaches in 2026, it is worth reflecting on how far we have come. The first network camera, launched in 1996, delivered one frame every 17 seconds—not impressive by today’s standards, but groundbreaking at the time. It did something that no analog system could: transmit video over a standard IP network. Read Now

  • From Surveillance to Intelligence

    Years ago, it would have been significantly more expensive to run an analytic like that — requiring a custom-built solution with burdensome infrastructure demands — but modern edge devices have made it accessible to everyone. It also saves time, which is a critical factor if a missing child is involved. Video compression technology has played a critical role as well. Over the years, significant advancements have been made in video coding standards — including H.263, MPEG formats, and H.264—alongside compression optimization technologies developed by IP video manufacturers to improve efficiency without sacrificing quality. The open-source AV1 codec developed by the Alliance for Open Media—a consortium including Google, Netflix, Microsoft, Amazon and others — is already the preferred decoder for cloud-based applications, and is quickly becoming the standard for video compression of all types. Read Now

  • Cost: Reactive vs. Proactive Security

    Security breaches often happen despite the availability of tools to prevent them. To combat this problem, the industry is shifting from reactive correction to proactive protection. This article will examine why so many security leaders have realized they must “lead before the breach” – not after. Read Now

  • Achieving Clear Audio

    In today’s ever-changing world of security and risk management, effective communication via an intercom and door entry communication system is a critical communication tool to keep a facility’s staff, visitors and vendors safe. Read Now

  • Beyond Apps: Access Control for Today’s Residents

    The modern resident lives in an app-saturated world. From banking to grocery delivery, fitness tracking to ridesharing, nearly every service demands another download. But when it comes to accessing the place you live, most people do not want to clutter their phone with yet another app, especially if its only purpose is to open a door. Read Now

Most   Popular

New Products

  • Luma x20

    Luma x20

    Snap One has announced its popular Luma x20 family of surveillance products now offers even greater security and privacy for home and business owners across the globe by giving them full control over integrators’ system access to view live and recorded video. According to Snap One Product Manager Derek Webb, the new “customer handoff” feature provides enhanced user control after initial installation, allowing the owners to have total privacy while also making it easy to reinstate integrator access when maintenance or assistance is required. This new feature is now available to all Luma x20 users globally. “The Luma x20 family of surveillance solutions provides excellent image and audio capture, and with the new customer handoff feature, it now offers absolute privacy for camera feeds and recordings,” Webb said. “With notifications and integrator access controlled through the powerful OvrC remote system management platform, it’s easy for integrators to give their clients full control of their footage and then to get temporary access from the client for any troubleshooting needs.”

  • Connect ONE’s powerful cloud-hosted management platform provides the means to tailor lockdowns and emergency mass notifications throughout a facility – while simultaneously alerting occupants to hazards or next steps, like evacuation.

    Connect ONE®

    Connect ONE’s powerful cloud-hosted management platform provides the means to tailor lockdowns and emergency mass notifications throughout a facility – while simultaneously alerting occupants to hazards or next steps, like evacuation.

  • PE80 Series

    PE80 Series by SARGENT / ED4000/PED5000 Series by Corbin Russwin

    ASSA ABLOY, a global leader in access solutions, has announced the launch of two next generation exit devices from long-standing leaders in the premium exit device market: the PE80 Series by SARGENT and the PED4000/PED5000 Series by Corbin Russwin. These new exit devices boast industry-first features that are specifically designed to provide enhanced safety, security and convenience, setting new standards for exit solutions. The SARGENT PE80 and Corbin Russwin PED4000/PED5000 Series exit devices are engineered to meet the ever-evolving needs of modern buildings. Featuring the high strength, security and durability that ASSA ABLOY is known for, the new exit devices deliver several innovative, industry-first features in addition to elegant design finishes for every opening.