By: Anthony Zotti
As a residential integrator, you’ve spent countless hours learning the ins and outs of Dolby Atmos, HDBaseT, how to dim LED fixtures, the nitty gritty of your chosen control platform and more. Commercial systems integrators invest in similar countless hours educating themselves on sound reinforcement, staging, video walls, video conferencing products, the nitty gritty of their chosen control platforms and more. Countless. Hours. The respective lists are long, sometimes overlap, and always require significant commitments to training. One system that both residential and commercial AV and control systems professionals rely on and should be actively focused on is the network.
Sadly, and despite many years of industry banter about “convergence,” I believe we have a long way to go.
Raising the Noise Floor
I recently attended an informal meeting with a prominent lighting control vendor, manufacturer’s reps and dealers. We were discussing wireless communications and the vendor’s upcoming plans to use 6LoWPAN, a wireless protocol that resides in the 2.4GHz frequency spectrum for device to device transmission. Their intention to use yet another non-Wi-Fi protocol in the 2.4GHz range concerned me and I said so.
It the issue would be caused by the high probability of simultaneous, interfering transmissions. 6LoWPAN packets can’t be demodulated by Wi-Fi devices on the same 2.4GHz band and, therefore, they would be adding to the overall noise floor, increasing interference. This is because 802.11 Wi-Fi uses a “listen before you speak” mechanism known as Carrier Sense Multiple Access, Collision Avoidance (CSMA/CA) that relies on the ability to demodulate 802.11 frames present and waiting until the RF medium is clear before transmitting. This vendor’s plan to utilize 6LoWPAN, an 802.15.4 protocol, has the potential to decrease performance of both the vendor’s equipment and the Wi-Fi networks already installed in the same and neighboring structures.
The 2.4GHz band is often described as the ’junk band‘ because it is shared by so many competing, non-cooperative technologies. Along with the aforementioned Wi-Fi and 6LoWPAN, additional examples include wireless handsets, analog video transmission, Bluetooth, Zigbee, and Z-Wave. All of these technologies coexist on the shared medium, namely air, but not without the potential to interfere with one another. Why are there so many protocols and communication technologies using that band? In the US, it’s part of the free, unlicensed ISM (Industrial, Scientific and Medical) band under the jurisdiction of the FCC. The ISM band is free to use but not without regulations or some caveats. One such critical directive is the concept that devices must accept interference from other sources.
I made the argument that a case could be made for using Wi-Fi instead of other competing protocols on the same frequency. Yes, Wi-Fi chips require more power. So what? We were talking about lighting control products that would, by necessity, be powered over wire. Yes, 802.11 is meant for transporting large amounts of data while 802.15.4 protocols are designed for sending the small amount of data needed for the vendor’s product. We’ll have overhead for the product to grow into if desired. The real issue is that by using 802.11 frames, we can utilize the benefits of CSMA/CD to allow their product to coexist with the WLANs for which we’re responsible. Sure, we would have to share precious airtime but at least we’d be sharing. We wouldn’t be stepping on one another’s toes.
We went on to discuss how the network could be optimized to most efficiently pass typical Wi-Fi data frames while segregating the vendor’s control and feedback frames. Specifically, we talked about the need to divide the WLAN into separate segments/broadcast domains by configuring VLANs; and that’s when things got really interesting.
Standing on Our Own Two Feet
In response to my case for a more advanced WLAN design, 25-year industry veteran and respected rep, Dave Thomas of the Momentum Group argued that vendors shouldn’t rely on the LAN/WLAN until networking vendors make it easy for integrators. He suggested that too many dealers aren’t prepared to manage networks at such a high level unless it’s done for us by network vendors that cater to us. On these points, I had to agree and disagree. I agree that far too many integrators have not invested in the training, capable gear, testing, and time necessary to properly deploy well designed networks. I see it far too often. Instead, I see dealers relying on vendors and third parties to do the hard work for us and this is where I disagree with Thomas. I don’t subscribe to the idea that third parties should be holding our hands through something as fundamental as networking. I believe that the responsibility is ours as dealers, technicians, and trusted value added resellers. The onus is on us to invest in our knowledge base and experience.
The AV and control industries have reached a point where we are now the target audience of otherwise unknown network vendors. These are firms that have virtually zero exposure in the larger IT industry and have no apparent traction outside of the AV and controls spaces. One such company describes their products as “designed exclusively for custom installers.” What does that even mean? Is it an indication that we, as an industry, aren’t educating ourselves on networking standards, topologies, designs, configuration, maintenance and install techniques? Are we so far behind that they are a legitimate crutch upon which we should be leaning? Are these companies taking advantage of our weakness?
I don’t think so. These companies are doing what companies do. Selling a product to willing customers. Do they really add value? Personally, believe that what they really offer is an opportunity. An opportunity for us to hold up a mirror and think long and hard about our capabilities. If we are willing to work hard, train, and practice, we’re able to create incredible electronic environments out of ridiculously complicated equipment. Why aren’t we able to do the same for the networks upon which our systems communicate?
The fact is we don’t need others to prop us up. We have the responsibility to better ourselves. Our clients have high expectations and unless we are well grounded in the fundamentals of our craft, which includes our LANs/WLANs, we are doing them a disservice. Educational opportunities abound. Test labs are an inexpensive way to improve our skills. We have strong social media channels with which we can bounce ideas off of one another. When we take these steps and learn how to support ever more capable networks, we open the doors for vendors to confidently bring to market products that we can reliably place on them.
By: Anthony Zotti