The Internet Of Things (IOT) is a fantasy world full of jargons and buzz words. But in reality, it is much simple if we understand the basic concepts well. I request you to read through my earlier articles to understand the basics of IOT, building blocks of IOT, IOT architecture and protocols in IOT.
In the previous article, we looked at the different protocols that are used in IOT layer wise.If I may draw your attention to the link layer, you may see some protocols stacked up there. What are they used for? Which one to choose? Let us explore these in detail through this article.
We all know that the amount of information available to use these days is mainly due to the connectivity of devices, including computers, mobile phones, servers etc. The level to which these connections are exposed determine the open availability of data. For example, in a closed network, the data might be available only within that particular network range whereas in the case of internet, it is available everywhere.
You get the point? Let me illustrate you with an analogy. In your home, if you want to connect your laptop with a PC and mobile phone, you will establish your Personal Area Network. If you are in an office or school intranet, you can connect with any of the devices within that network (LAN) to send and receive data. But, somebody outside of this network would be completely isolated, right? Now, assume that you have your office in 10 locations across the world. You might consider changing your LAN to a WAN (Wide Area Network) to provide extended access.
When you build this outward, you venture into a wider network connecting a wider audience ultimately connecting various devices incrementally thereby offering more data. Well, if you have understood so far, let us get into our topic for today.
Wifi, Wimax, IR, NFC, Bluetooth and ZigBee are short range communication wireless protocols that you can use to construct your networks. Though, all of these are used for a similar cause, they differ with their operational nature.
Let’s take the case of Wifi. It is used for connecting our personal devices through a router.This can be used for high amount of data transfer, but it is a bit power consuming and thus works out costlier. There is also a range limit, may be 300 feet depending on the router that you use.
Wimax is very similar to Wifi but it is much faster and thus even costlier. Wimax can have a range of upto 30 miles.
IR and NFC are line of sight protocols as the devices that need to communicate through IR and NFC need to see each other. Your television remote or AC remote need to be held straight in front of the device to make it work. Similarly, if two mobile phones need to communicate through NFC, they need to be brought together. Here, the amount of data transferred is very less.
Bluetooth is better than IR and NFC as it allows a much wider range up to 10m and you don’t need to have the devices face each other. You can mostly transfer files through Bluetooth. The hands free set for your mobile, wireless mouse, keyboard etc can make use of Bluetooth.
Zigbee is not as prominent with the layman as it is with the technicians. Infact, most of the devices that we use today have Zigbee inside them. Zigbee is nothing but a protocol that operates through a modem and a module. There are various types of Zigbee modules for various use cases.
Zigbee is also a short range protocol that works upto 50 meters. It utilizes low power but transfers data slowly (low bandwidth). Why you need to use Zigbee then? Because it brings on lot of savings in the form of battery life and cost. When you want billions of devices to communicate together, cost is a very essential factor.
Practically, there are many vendors who manufacture Zigbee compliant modules(Xbee being one of them). These modules can be plugged into a microcontroller board like Arduino that has a USB port to connect with your computer. It also has a driver program for installation. Once installed, you can do various programming through specific languages.
To give you an idea of how they look like, I request you to take a look at the below images
Arduino board with Xbee module plugged in.
That’s it for today. Hope you understood the use of various protocols in the link layer and specifically Zigbee. It is very important to understand these as IOT will make heavy use of these technologies. Thanks for reading and hope to meet you with the next article.
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