7 Communication technologies revolutionizing the IoT

Communication technologies revolutionizing the IoT

As discussed in an earlier article, the Internet of Things (IoT) can be summarized to consist of the following:

1. The ‘Thing’/object to be connected to the Internet- this can be your green house, home ground security situation (for a surveillance system), your house environmental conditions, and your gadget e.g. Umbrella, your animal e.g. dog or cow.
2. Sensor(s) and/or sensor networks- these are for sensing the particular parameter/condition to be monitored. For example a soil humidity and a temperature sensor for sensing the soil humidity and temperature of your farm. As another example, a passive infrared (PIR) motion sensor for sensing the presence and movement of any object emitting infrared radiation e.g. a human being.
3. A control unit-microcontroller is the main control unit. It is essentially a small computer on a single integrated circuit (IC) containing a processor core, memory, and a programmable input and output peripherals. The peripherals are controlled through several general purpose input/output (GPIO) pins. The microcontrollers also house analogue to digital converters (ADC or A/D converter) for converting analogue signals to digital signals that the core processors can understand. Lastly, they have timers for timing events handling done by the processor cores.
4. Communication modules- (this is the core of our today’s discussion) these generally consist of embedded electronic modules that implement the communication (by transforming the data received in bits and bytes into radio waves or signals that are transferred by wire or wireless to the Internet (specifically to data management platforms for IoT e.g. ThingSpeak, and Thingworx platforms).
5. IoT data management platforms- the following has to be understood; data is a very raw stuff generally, and is absolutely meaningless if nothing substantial to the user can be derived from it. To aid in understanding, consider Facebook visits per day. Having a number like 250million visits per day is generally meaningless; but if you sit down and start analysing that big number, the sources that generate it, and the drive behind the big number then much stand to be gained. This (what to be gained) is termed ‘information’. Yet information is also useless to an ignorant fellow or if it cannot be understood by the intended recipient. Consider an alien visit from space; if they send communication signals that the earth’s technologies cannot understand then that information is entirely useless; the earthlings stand no chance of understanding whether the info was a threat, a ‘friendly’ greeting, or a ‘disease over the Internet'. If we can understand it then we have what we call ‘knowledge’. Knowledge plus practice over and over (experience) culminates into ‘wisdom’. The IoT platforms like Thingworx, ThingSpeak solve the above mysteries.
6. Web of things- (IoT data management platforms is also part of this). They provide the human interfaces for interacting with data. Some include mobile applications for user updates. Others also provide platforms for controlling (remotely) the IoT systems. The ‘Things’ connected to the Internet generate large amounts of data and considering that there will be about 50billion things connected to the Internet ( a device to human ratio of 7:1 if the population will be 7.5billion then) by 2020, this enormous amount of dynamically changing data is termed Big Data. There is, therefore, a need to have a separate data management system for the same, separate from that of the conventional Internet of Computers for your YouTube, pdfs, and HTML documents.
7. Actuators and/or actuator networks- knowledge gained from IoT data management platforms is applied here. IoT wisdom too is gained from here. Consider your body; it is absolutely useless if you can sense the pain from being burned by fire but you are unable to anything about it. As if you are a tree, you sense being cut but you can do nothing about it (except for ‘enchanted’ trees of course) but stand until it is your time to fall. To do something about a sensed condition is to ‘actuate’. This is what actuators are for. In IoT, they include motors for starting a water pump in a smart irrigation system, cameras for photo and video capturing in case an object is detected.

Mysteries having been demystified, let's jump to the core topic of today, the communication technologies that are enabling the ‘Internet’ part of the IoT.

1. Radio Frequency Identification (RFID)

This is a very common technology in use today. It was initially introduced for identifying and tracking objects with the help of small electronic chips known as tags. You might have heard of it being used in tracking assets like your wanderer pet dog or identifying objects like the physical you in your workplace (one can steal your tag and of course the technology will still identify them as you). For each RFID tag, a unique ID number is assigned. So if an ID is linked/associated to you (let’s say a sales manager) in a workplace through the tag you put around your neck and hang it on your breast, if you swipe that tag through a RFID reader (linked to the employees database ID numbers), the machine will identify the individual as the you/sales manager and the door will be opened for you.

Types of RFID chips:

1. Passive-they do not have power sources, and cannot transmit or receive on their own. They are power activated by the minute signal sent by the RFID reader. They transmit only a small amount of information (the ID number).
2. Active-they have their own battery and can transmit data continuously.
3. Battery Assisted Passive (BAP)-this is a hybrid of both the passive and active chips. It carries a battery but can only transmit data in the presence of an RFID reader. The battery assists in long distance data transmissions.

RFID tags alone can be used to build an IoT-like network, but their proximities are so limited to just a few centimetres. It also cannot provide any direct connection to the Internet and an intermediate node (a computer) has to be sought.

2. Bluetooth

Named after the tenth century Danish King Harald Blatand, which translates to Harold Bluetooth in English, Bluetooth is a technology standard for exchanging data over short distances. It uses short wavelength radio transmission in the ISM band from 2400MHz to 2480MHz. it can be used by fixed and mobile devices for creating personal area networks. 

It has low power consumption, devices can discover and communicate with each other without the need to be in visual line of sight (as in the case of Infrared). It, however, cannot provide direct connectivity to the Internet, and an intermediate node (e.g. PC) is needed for the Internet.

3. ZigBee (IEEE 802.15.4)

This is the latest and one of the most advanced wireless technology. It is an open global standard to address the unique needs of low cost, low power wireless networks for inter-device communications.

The standard operates in unlicensed bands including 2.4GHz, 900MHz, and 868MHz. it can have a low power consumption of 50mA, a maximum data rate of about 250kbps and the communication range can range between 100m and 1km (max) depending on the output power. Peer networks can also be created. However, it still requires a gateway link with Internet connectivity e.g. PC.

4. Wireless Fidelity (Wi-Fi)

It is the IEEE 802.11x standard, and undoubtedly the most common way to connect devices wirelessly to the Internet. Wi-Fi networks are very easy to establish and thus IoT devices Wi-Fi modules, like the one shown below, can have direct Internet connectivity without an intermediate node.

a Wi-Fi module

However, its only drawback is that it is more power demanding than other solutions.

5. Wired communication (The Ethernet)

The only plug and play Internet connectivity available since the ARPANET ‘ha-ha’ moment. The Ethernet protocol is a well-established one and can achieve very high data rates of up to gigabits/gigabytes per second (Gbps/Gbps). 

The range is only limited to how long your cable is. It does not require as much power as the wireless communication. As you know, it does not provide mobility at all but you never have to worry about signal strengths. If it was meant for 100mbps, it will deliver at 100mbps, save for unforeseen, but detectable and avoidable problems such as data collisions, thanks to Carrier Sense Multiple Access with Collision Detection or Avoidance (CSMA/CD or CSMA/CA) technologies.

6. Cellular Networks: The Mobile Internet

It is simple, the access of the Internet from a mobile device e.g. smartphone or laptop through a mobile broadband network. The broadband network depends on the same electromagnetic (EM) waves’ technology that your phone uses for serving calls and messages.

GPRS, 3G, WirelessMaximum (WiMAX), and 4G (esp. the LTE), are the various existing network standards for serving mobile Internet.  Depending on the standard used, the speed can vary from 80kbps (for GPRS) to a few Mbps (for 3G and 4G). The communication protocol is complex, and in addition to high power requirement where the reception signal is low, the battery power consumption of mobile Internet-enabled devices is generally an issue. Still, it is a good option for connecting devices directly to the Internet as no further infrastructure is required.

7. Radio Frequency Links (RF-Links)

This involves the use of simple radio frequency interfaces. They are quite cheap and small and can provide communication range from 100m to 1km, depending on transmission power and antenna used.

They, however, do not provide any implementation of the TCP/IP communication protocol (or just any other communication protocol). So, you have to create your own protocol for communication, identifying devices with each other and making sure that all the information you have transmitted is delivered. Data rates are up to 1Mbps but still a gateway node e.g. a computer is needed for internet connectivity.

The following table summarises the basic characteristics of the above-discussed technologies. They will help you make a decision on the best technology to use for you IoT project.