[cc438]

The issue of radio spectrum is glossed over in a short bullet-point summary at the end of the article while I believe it deserves to be the article's thesis. The limitations imposed by the radio spectrum and its availability are at the root of every other point made by the author.

You just can't have high bandwidth, excellent protection from interference, and low energy usage all at once. The blcoks of spectrum that offer the best balance of those qualities are already booked up for things like OTA TV broadcasts and "high-cost and high-powered cellular" networks. The issues with mesh networking are also immediately apparent if some classes of device are to be kept on separate networks or have to forgo their role as a node due to the power requirements of a repeater.

A simple example for what airwaves would look like in the crowded "IoT' future is your average apartment complex and the 2.4ghz spectrum. 30+ routers competing for the same tiny space absolutely destroys the quality (latency, throughput, power draw from the devices radio) of the connection. The space is so crowded that you may only see 5-10 networks as the signal from a router 2 stories up is so dirty that you can't even receive the SSID but the interference is still there.

There is only so much spectrum available for use, even if it was all unrestricted. There won't be a mass adoption of networked "things" until someone is able to find a loophole in the laws of physics.

[patburns]

I covered this in a separate piece on low power wide area networks http://www.slideshare.net/haystacktech/the-iot-hunger-games-... though to be clear, we are not talking about high bandwidth like Ethernet. We are seeing good signal propagation in sub-1GHz bands (measured in miles) while preserving multi-year AA battery life with some newer PHY layer technologies like LoRa and others. 2.4GHz is a mosh pit that most serious IoT vendors are fleeing due to the high interference and the resulting RMA's and related costs. For sensor networks, there is rarely a good reason not to use one of the more popular sub-1GHz bands 433/868/915 regardless of your geographic location.

[bsder]

> 2.4GHz is a mosh pit that most serious IoT vendors are fleeing due to the high interference and the resulting RMA's and related costs.

Your sales hyperbole is drowning out the good points you have. Knock it down a notch.

2.4GHz is a mosh pit. However, nobody is going away from it precisely because you need it to bootstrap the network. Data is most useful when it hits the internet, and, for better or worse, the only cheap way of doing that is WiFi with the occasional side of Bluetooth Low Energy with an attached phone/tablet/etc (however, people get annoyed at the extra battery drain).

Now, if you convince Apple or Google to throw 433/868/915 chips into all their devices, then, yes, people will dump 2.4GHz like a hot potato.

Good luck, but I won't be holding my breath.

[patburns]

"2.4GHz is a mosh pit. However, nobody is going away from it"

Nobody strikes me as hyperbole, really. You will see one of the two companies you mention embrace sub-1GHz in the next 6 months. Also LPWAN's are almost entirely driven by sub-1GHz now and the list of participating telco's are not nobodies.

[darkmighty]

I found some of your claims a little hard to believe. 1km+ range behind walls?

Do you have any test data to confirm this? Is there a device that can be acquired that has implemented your specification?

[jpnorair]

It is a feature of using lower frequencies together with lower data rates and signal processing technologies. Consult with any RF engineer -- there is no magic here, just practical engineering to solve a particular set of problems.

[simoncion]

Would you be so kind as to un-shorten this URL? URL shorteners poison The Web. :(

[patburns]

done - thanks!

[anotherhue]

It's not quite that bad as the channel time requirements for most IoT applications are small. I did some research on this (https://github.com/hughobrien/wlan-stats) but it's far from complete.

[patburns]

When your wireless technology has an average outdoor range of 30-40 feet, of course spectrum is not an issue. When large numbers of endpoints (thousands or tens of thousands) share a common access point over many miles, it's a really significant issue that can be addressed in a number of ways outlined here http://bit.ly/1hExgtG

[anotherhue]

I thought DASH7 was dead. Glad to see those rumours were exaggerated.