The roof, the roof, the roof is on IP

What is Digital Ceiling?

Looking back at the evolution of the network in the past decade, we see a constant trend of devices migrating to Ethernet, resulting in a migration to IP. IP telephony took off in 2005 and is now the de facto standard for any phone system. Coax-connected cameras migrated to IP surveillance in the late 2000s. Legacy building management systems using BACnet started migrating to low-voltage PoE systems in the early 2010s. Within the past year, we’ve seen a new trend of high-voltage systems like lighting start migrating towards low-voltage PoE, dubbed “Smart Lighting”. This move towards digitization makes sense on all fronts. It’s cheaper, scalable, extensible, can easily be managed and monitored, and opens the door for new experiences with intelligent buildings.

As the Internet of Things continues to proliferate, our buildings will naturally transform, becoming smarter and more interactive. Our lights, HVAC, thermostats, cameras, digital signs, wireless networks and security systems will work in unison, making intelligent decisions, and securing environments while reducing environmental costs. This is the frontier that Cisco is calling the Digital Ceiling.


How is Cisco involved in this frontier?

When we talk about building automation, we are talking about IoT, introducing devices to a network – devices that traditionally were not connected. Moreover, when we talk about IoT, we assume that all devices are connected. In an IoT building, we’ll be connecting typical devices like cameras and wireless access points, but more importantly, we’ll be connecting lights and sensors.

Connected lights have several interesting use cases:

  • Reduced costs using ambient lighting when detecting external light through a window;
  • Reduced costs using detection of movement and behavior;
  • Dynamic color, intensity and tone changes depending on location or motive (i.e. as I like to call it: human mood manipulation);
  • Guide paths by light.

Connected sensors have even more value:

  • Proximity sensors offer superior location services;
  • Temperature sensors collect data for precise HVAC control;
  • CO2 sensors collect data aiding in environmental security and measuring carbon emissions;
  • Bluetooth low energy (BLE, BTLE) “beacons” provide scary accurate location services and can also collect valuable information from devices with bluetooth enabled.

Holistically, the idea behind a unified building under the Digital Ceiling portfolio leads to some intriguing benefits:

  • Heating and cooling systems that account for actual occupancy in an area of the building
  • Signage and way-finding that automatically connects to and informs visitors’ personal devices;
  • Continuous monitoring of building access points for both security and traffic data;
  • Occupancy and area usage that’s tracked to inform better space utilization and configuration.

Getting Lights and Sensors on the network

Cisco needed a way to get lights and sensors on the network, and be able to do it in a cost effective way. Rather than wasting resources by running cables between data closets and each of these devices, Cisco is introducing a new switch for the ceiling. This was a possibility in the past with compact switches fixed to a wall bracket, but realistically compact switches were not designed for these environments. Last year when Cisco set out to design a switch in the ceiling, they considered placement, power, cooling, size, construction and building code. What this resulted in is a new purpose-built switch, designed with all of these considerations in mind. Although the switch is currently in prototype, Cisco is expecting a release in Q4 of 2016.

A few bullet points about this switch hardware:

  • 10 port switch (Eight 100M 60W UPoE ports, and two 1G uplink ports)
  • 1 console port
  • Completely fanless. (This is a feat considering the significant heat generated by powering 8 devices at 60 Watts. The switch is essentially a giant heat sync.)
  • Plenum certified
  • Powered via junction connector or standard power.



The last point in the bullet list above is important – “powered via junction connector”. It’s common in any building to have junction boxes all over, providing connectivity back to house power. Electricians install normal electrical junction boxes, and slap the necessary plate on top depending on the required connection type.


Similar to this, the Cisco method will utilize a junction plate that has a proprietary connector on it in, allowing you to easily insert and lock the switch directly onto the junction box. The connected switch powers up. Easy as that! Next, electricians would normally wire light and sensors back to some central building automation controller. Instead, electricians will wire these devices directly to the newly installed junction-box switch. Righteous.

No photos of the switch have been release yet, but I imagine it will look something like Cisco’s industrial switches, only slightly larger and purely Ethernet:



These devices are running IPv6, and can be uplinked to your network using the standard uplink ports. Similar to a controller-based wireless network, you have a zone controller, and your series of access switches all members of the same “zone”.

LLDP is used to rapidly bring endpoints online and provide a standardized method for future development. If a switch reboots, it won’t matter, as cached LLDP speeds power-on operations, resulting in sub-second “blip”. Hardly enough for your eyes to notice. This is a fail-open systems from the layer 2 perspective. 


Notice the zone cloud in the picture above. Something else I’d like to point out is the capability to connect these switches in a ring. You can run cabling infrastructure between your switches in the ceiling, and simply run a connection or two back to your Corporate infrastructure. This reduces cabling costs and security surface area, and still grants full visibility to the Digital Ceiling.


Digital Ceiling infrastructure uses Constrained Application Protocol (CoaP) as it’s core protocol for operations. A server instance will be embedded on each switch, and will run as a proxy to all of the IoX devices behind it.

CoaP is to UDP what HTTP is to TCP. It follows very similar GET-style methods, just over UDP.

Much like HTML being used over HTTP, CoaP also has it’s own markup language called SENML (Sensor Markup language). SENML is the document format for CoaP.  


Cool thing is, Cisco has developed very familiar CLI interface to interact with the device, providing users with a comfortable means for interacting with the devices.  If you have ever logged into a Cisco switch, this will look strikingly familiar:



Cisco has a long-running history of innovation in the building and energy management realms (remember EnergyWise?).  They announced strategies and solutions for Smart buildings 7 years ago, with energy management capabilities in IOS-devices existing over a decade ago.  However, this has yet to gain solid traction.  This has me thinking.  Is Cisco wasting it’s time and resources in this realm?  Or, is Cisco a bleeding-edge pioneer in this industry, providing continued solutions even though market demand is currently small, understanding it has potential in the years to come.  Arguably, this could go either way.  I agree with Tom that this is a risky market; it’s clever enough to make sense in particular scenarios, but niche enough to fall out of practicality, thereby falling out of building design discussions.  

As an engineer and architect, I have experience with new construction, but never have I been in on the conversations surrounding lighting.  This is a huge shift, and Cisco is going to have to get intimate with building architects and contractors in order to influence this change.  This said, I still love the idea of a digital ceiling (although the name could be better).  I’m optimistic.  The measurable benefit you gain regarding reduced energy consumption, actionable analytics, and unique value-adds for customers will be the ticket that sells this solution.  I’ll be staying tuned to see how this develops over the next few years.

More information

Check out the fantastic presentations given at Tech Field Day at CLEUR/Berlin 2016:

Cisco Digital Ceiling Introduction with John Baekelmans from Stephen Foskett on Vimeo.


Cisco Digital Ceiling Design Discussion with John Parello from Stephen Foskett on Vimeo.

David Varnum


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