IoT 표준을 위한 개발자 가이드

https://stanfy.com/blog/developers-guide-to-iot-standards/

Developer’s Guide To IoT Standards

Posted on May 28, 2015 by Andrii Degeler

Internet of Things may seem a young (and promising) industry but it has already started facing at least one problem typical for older ones. The problem is standardization, or rather lack of thereof: currently there’s a bunch of different platforms fighting, with new ones mushrooming every month or even more often.

The need for one standard to unite all the refrigerators, thermostats, cars, washing machines and other smart appliances is obvious. However, it seems like there won’t be just one winner in this war as too many players have already got some traction with manufacturers. As Z-Wave’s Avi Rosenthal put it:

“There will be a prevailing standard at some point. But it is going to take years, maybe 5-7 years, and I expect the standards will change over time.”

To navigate the rough sea of IoT standards, here’s a handy guide for developers gearing up towards building a new IoT appliance.

There are Bluetooth and Wi-Fi, so why bother?

Actually, quite a few players on the IoT scene don’t bother at all and just use the most widely adopted universal standards. It goes for all devices that would connect to your home Wi-Fi network, from Petcube to Amazon Echo, which also uses Bluetooth to stream music from mobile devices.

However, more sophisticated smart home devices like thermostats or energy monitoring systems, which need to interact with other appliances, need protocols tailored for their purposes. According to Jeffrey Kaplan, managing director of Think Strategies, usage of standards like Bluetooth and Wi-Fi raises questions of security, privacy, and efficiency.

Hence the fragmentation.

ZigBee

An open standard by IEEE dating back to 2003 with the later revisions from 2006 and 2007, ZigBee uses low-power radios to transfer data through mesh networks. That means that although the transmission is limited to 10–100 meters, it uses intermediate devices to pass the data further, so all the radios work as repeaters.

ZigBee is a good solution for those concerned about security: the mesh networks are secured by 128 bit symmetric encryption keys.

There are quite a few ZigBee-compatible devices on the market, however some say that gadgets by different manufacturers may have difficulties communicating with each other.

Z-Wave

This standard has the largest installed base of products at the moment, even though it’s a proprietary one owned by Sigma Designs. The standard also uses power-efficient radios and mesh networks but works on the 908.42 MHz frequency, while its rival ZigBee runs on the 2.5 GHz.

Z-Wave Alliance’s Raoul Wijgergangs says that ZigBee’s frequency is also used by Wi-Fi, which makes the spectrum much more cluttered. Less cluttered spectrum, in his opinion, can mean reduced power usage and fewer attempts that have to be made to send the data between radios.

The fact that Z-Wave is today’s market leader doesn’t mean anything if we think about the future. For example, the recent Samsung’s IoT chip Artik does not include support for Z-Wave, but will work with Wi-Fi, Bluetooth, Zigbee, and Google’s Thread.

Thread

One of the younger standards in the IoT world used by the Google-owned smart home appliances startup Nest. The working group behind the standard includes Samsung, ARM Holdings, Freescale, Silicon Labs, and Big Ass Fans. Thread creates an IP-addressable mesh network with up to 250 devices that supports cloud access and AES encryption.

Like ZigBee, it’s an open standard built on top of IEEE 802.15.4 wireless protocol; recently the two working groups even announced plans to collaborate on creating a unified solution with ZigBee as a network layer and Thread as an application layer.

Apparently this one is worth looking at if you’re thinking about building something that’s going to need to communicate with core smart home appliances. Also, betting on something backed by Google doesn’t seem a bad idea.

HomeKit

But here comes another standard backed by a big name in the industry: Apple’s HomeKit. It’s not available for customers yet but we know quite a bit about the standard already.

HomeKit is supposed to be a platform that unites Apple-made and Apple-certified devices via Wi-Fi and Bluetooth. Apple has already revealed a list of partners that includes iHome, Haier, Withings, Philips, iDevices, Belkin, Honeywell, and Kwikset.

HomeKit is not compatible for any other standards per se, though Apple has announced a hardware bridge that could be used to connect non-HomeKit devices that use ZigBee or Z-Wave with a HomeKit network. There are, however, numerous limitations to the range devices that can be bridged: basically, the only way to make sure your product will work with HomeKit is by receiving an MFi (Made For iPhone) license from Apple.

 

In addition to these four standards, there are several minor ones, as well as recently announced platforms we know nothing about, like that by Huawei. None of the current standards is perfect, which means that with the rapid increase in numbers of IoT devices we’ll see new entrants in this market.

As of today, however, it makes sense for IoT developers to look at the biggest players fighting a Battle Of The Four, with the battlefield being our own homes and hardware manufacturers’ preferences.

There’s another war going on, too — that of hardware platforms that can be used to power various Internet of Things appliances. This will be the topic of one of our next posts. Stay tuned!