by Colin Berkshire

In 1982~1983 I had the pleasure of sitting in the next cubicle over from one of the people who refined the twisted pair ethernet standard we now have. He was a voting member of the standards committee working on the 802.3 ethernet specification. We worked at BNR (Bell Northern Research) which was a part of Bell Canada and Northern Telecom at the time. He believed that eventually everything would be connected to Ethernet. Not only computers but also phones and security and cameras and building energy control systems and everything. He was brilliant, and he had a vision for ethernet that is now coming to full fruition.

Fast forward to today…

As an experiment our company just installed some Ethernet office lighting. Yes, I mean light fixtures installed in the ceiling. I was profoundly skeptical of the whole thing. Boy did my thinking change by the time this experiment was over.

First, we installed an LED Troffer. These are the 24” x 48” lights that sit in the suspended ceiling grid that traditionally have 3 or 4 fluorescent light tubes. The fixture looked no different than any other, except that the light was more evenly disbursed across the lens. But the real surprise was how bright it was. Putting out 1,500 luminous it was only about half as bright as a 4-tube florescent light, but still plenty bright. It was an “economy” model intended for low cost mass market lighting.

Next the representative showed me what is now a high-end fixture that he believed would eventually become the standard. This 24” x 48” troffer put out a respectable 2500 luminous, or roughly the brightness of 3½ times what a 75 watt incandescent bulb produces.

What was shocking was that these fixtures had ONLY an RJ-45 connector on the end. That was it. They were powered entirely over ethernet (802.3 POE+). The wire from the fixture just went back to the network switch we supplied. My mind had a difficult time thinking of general lighting being something that your POE switches had anything to do with.

I asked about cost. (These were pre-production units.) I was told that while today the cost of POE lighting is higher than 120v lighting, this won’t be the case for long. The volumes are such that costs will plummet. The cost to produce a POE troffer will be less than a 120V troffer because there are significantly less materials—both electronics and metal.

Just as I was grasping the idea of powering all office lights using Ethernet the real demo started: The rep pointed a camera out the window and plugged it into the hub. He explained that the brightness of the lights would be balanced with the ambient lighting streaming in the windows and the brightness outside. People need a certain amount of light, but it is within a range. When the sun is very bright outside they need more light in the core of the building and less from overhead. The camera allowed the brightness of the ceiling troffer to be continually adjusted in brightness. The troffer closer to the window would be dimmer and towards the core of the building they would be brighter.

There is obvious energy savings possible by individually dimming each troffer according to localized need.

He explained that as clouds pass over the ambient brightness through the windows changes. The troffer respond according by supplementing light levels but also by adjusting building core brightness. The result is a space that feels much more “outdoorsy” and less sterile. Like the earth itself, it felt alive and fresh. The pulsations of brightness made me want to get out of my office daze and start thinking.

But the show wasn’t over. He slid a filter over the camera lens to simulate evening and the room became brighter AND the color of the lighting changed to a warmer glow. During the day the troffer provide 5000K light which matches the sub. In the evening the troffer gradually changed to 3000K, which is more yellow and fire-like.

I asked if each light fixture needed to be home runner to the networking closet. The rep explained that this wasn’t the optimal arrangement. The optimal arrangement is to install a POE switch up in the ceiling plenum and to wire the lights in a star from that point. There would be a single ethernet connected to the plenum switch that connected it to the network.

I am now realizing that lighting is going to fundamentally change in the next few years. It’s going to get smarter, it’s going to save energy, and it’s going to feel better. But now I am pretty convinced that office lighting is going to use POE and connect to our network.

And how does this relate to telecommunications?

If you think that communications is about phones you are thinking like buggy-whip manufacturers. Every one of those ceiling light fixtures is a new communications opportunity. They use ethernet, RJ-45 connectors, they communicate, and they are complex systems. I’m perfectly ready to accept office lighting into the “Unified Communications” fold.