Powerful New Development PoE
It wasn’t too many years ago that security dealers and systems integrators were first introduced to the term Power over Ethernet, or PoE, and the standard IEEE802.3af.
Now, just as they are starting to get acclimated to the new concept of providing power along with data in one line, the high technology world’s ever-continuing quest for additional power is helping usher in a new standard in PoE, IEEE802.3at.
According to Michael Pula, technical marketing manager with Tinley Park, Ill.-based Panduit, the Power over Ethernet (PoE) standard of 802.3af was ratified in June 2003, by the Institute of Electrical and Electronics Engineers (IEEE).
The technology’s creation resulted from “the need to support Voice over IP (VoIP) phones, in order to remove the need [for] a separate power cord or power supply going to those phones, making the user experience much like plain old telephone service (POTS),” Pula says.
The benefits of PoE largely flow from the fact that both power and data travel over the same copper lines, he explains. Those benefits extend not only to VoIP phones, but other devices traditionally requiring disparate wires for power and data. PoE can power cameras, alarm keypads, access control readers and fire alarm products, among others, Pula says. “Technologies such as VoIP, enabling system convergence, are fast becoming the norm,” he adds.
PoE provides another key advantage that is ever more important as businesses adopt greener strategies. In sharp contrast to traditional powering that is always “on,” PoE only provides power when a device is connected, helping conserve power. “Devices such as wireless access points that do not need to be on all the time can be remotely controlled and turned off during non-business hours,” Pula says.
A NEW STANDARD IN POEThe new standard, 802.3at, won’t be ratified until the IEEE meets in the first quarter of 2009 and approves the new standard by a majority vote, Pula says. Because it provides for almost twice as much power, lifting today’s standard of 15.4 watts to about 25 watts, it is designed to support higher power devices, he explains.
Wireless access points are an example of devices that will benefit from 802.3at. “Additional value can be added to wireless access points that adopt the new standard to provide greater range and higher data capacity to end users,” Pula says.
Other devices sure to reap greater utility include security cameras, reports Keith Hopwood, vice president of marketing and sales for Phihong USA Corp., Fremont, Calif., which sells power solutions to major OEMs worldwide. Many security cameras work on the lower watts provided under today’s standard, 802.3af. Those watts readily handle high resolution, high frame rate and pan-tilt-zoom functions, he says. But when applications call for heaters on cameras in cold and wintry applications, or infrared illuminators on cameras, more watts are required.
“There are people who can do things they never could do before, such as emergency exit lighting and four-color displays,” Hopwood says.
As manufacturers and building owners have seen the benefits of PoE for Voice over IP phones, wireless access points, security cameras, keypad readers and other such devices, “the need to extend the converged capability of power plus data to more power-hungry devices becomes evident,” Pula says.
DOWNSIDESPula believes the only limitation of the new standard will be alerting users to the potential of 802.3at generating greater heat than the previous standard did. There is “potential for additional heat that may be carried along the cabling, which traditionally would have supported only data but now supports data and power,” Pula says.
Hopwood, however, identifies a different downside of 802.3at. “It’s the increased complexity for the user, the integrator and the security dealer,” he observes. “There are a lot of products on the market designed for the old standard.
“And there are a lot of people who think PoE is PoE. They’ll say, ‘Now you’re telling me there’s a type I and a type II [of PoE]?’ The integrators will have to look very closely at the cameras they are using. Some say simply ‘PoE.’ When the new standard comes out, some cameras will say ‘802.3at,’ and the installer will have to either upgrade the networking equipment to incorporate that camera, or add a mid-span power injector that adds the high-power PoE into the network.”
Hopwood believes many simple cameras will continue to use the old standard. It will be devices with newer features that adopt the new standard.
“There are many pre-standard products on the marketplace,” he points out. “There also are many people in the security marketplace who don’t understand even the basic PoE. There are a huge number of potential applications for it. There’s a movement from analog to IP, but people need education in making that transition.”