Connecting technology is one cardinal aspect of an IoT Infrastructure. Because that’s what links and makes the ‘things’ talk on the ‘internet’. There already exist a good number of connectivity technologies which have been further evolving with time. Based on your requirements, you can decide on which one to use. The connecting technologies differ in their trade offs among power consumption, range, bandwidth, security and cost.
At the top most level, the connectivity technologies can be divided into – Wired and Wireless.
Wired technologies come with certain advantages like low power consumption, higher bandwidth, and higher security. Wired connections are further less affected by the surrounding factors like obstacles and interference from other electronic gadgets.
On the other hand, wired connections suffer a major concern of its range being limited by wiring length. The need for a physical medium has its own inconvenience. Then of course there’s the cost factor which is much higher for wired connections. Any damage replacement or repairing too comes at relatively higher rates.
The most commonly seen wired technologies include USB, Ethernet, HDMI etc. Among these, ethernet is the most widely used one. The fastest type of ethernet cable i.e Gigabit Ethernet offers a data transfer rate of 1000 Mbps whereas USB 2.0 offers a speed up to 480 Mbps.
One instance where wired connection can be more preferable than wireless ones is home automation where wireless connections can be prone to interference with too many WiFi or Bluetooth enabled devices installed in the vicinity.
As we know that the world is going wireless with nearly every possible electronic accessory like headphone, mouse etc., most of the real-world use cases of IoT demand a wireless connection. This explains the rapid growth of the wireless technologies over the years.
There are the traditional ones like Satellite and Cellular. Your smart phones are a good example of cellular connectivity. As you can see, they work over a large distance, and transmit a huge amount of data, but how frequently do you need to charge them? Thus, cellular connectivity has high range and bandwidth but not power efficient.
Satellite connectivity comes into the picture, when there’s no cellular towers in the vicinity. Thus, Satellite connectivity offers even higher range. Satellite connectivity has a chance of having a higher penetration in the future of IoT, due to its better coverage, reliability, longevity, a smaller number of local infrastructures.
Technologies for handling high data rate
Next comes the power efficient wireless technologies having limited range but fair amount of bandwidth like WiFi, Bluetooth Low Energy (BLE, as the name suggests is a power-conserving variant of Bluetooth), RFID, NCF, Zigbee, Ultra-Wideband (UWB) etc. Due to several convenience, majority of the IoT systems are being built on the above-mentioned technologies rather than the traditional technologies like Cellular and Satellite.
Examples of IoT applications where these technologies find its use are Indoor Positioning Systems, where precision i.e higher bandwidth is more important than higher range as the area to be covered would be confined.
WiFi, BLE, UWB and Zigbee provides a decent update rate and precision, which makes them an ideal fit for medical related IoT applications too. WiFi and Bluetooth, due to their ease of deployment, are two of the most widely used technologies in IoT applications. BLE’s major disadvantage is its limited range of 1-5m, which you might have witnessed while trying to transfer files on your phone through Bluetooth.
Among these technologies, UWB offers the best accuracy, so if precision is the requirement, then UWB is your answer. UWB is gradually gaining popularity due to it’s several advantages like high precision, energy efficiency and less probability of interference (due to its operating frequency of 3.1 – 10.6 GHz)
For use cases which requires a very short range, RFID and NFC are two options.
Technologies for handling low data rate
Then comes the technologies which consume less power by allowing a low data rate but higher range. Connectivity options in this group are called Low-Power Wide-Area Networks (LPWAN) or LoRaWAN. LPWAN is basically the umbrella term for any networking technology that can carry data over larger distances by utilizing minimal power. Sending of small amount of data at a time, enables LPWANs to operate at low power with a minimum range of 500m.
These technologies, designed specifically for IoT applications have emerged as a need to cater to the requirements of the more ambitious IoT projects like Smart Cities, Smart Factories, Smart Metering, Smart Parking Solutions, Smart Agricultural Practices.
If we take the example of an agricultural field, be it a moisture sensor or a crop disease detector, a frequent transmission of data isn’t required. But, in order to operate in the midst of an agricultural field, power efficiency is important as it would have to be battery operated. Thus, in order to transmit a small chunk of data from time to time in a large agricultural field, LPWANs would be the right choice.
“Today only 20% of the global population is covered by an LPWAN network”
Is it possible to skip the significance of connectivity?
As you might know that the chief components of an IoT infrastructure are – sensor/device, connectivity technology, data processing module and user interface.
The sensor(s) or the device would be collecting data from the ambience. The connecting technologies would take this data for processing, usually to the cloud. Now, what if there’s no need to carry data a long way for being processed? What if the processing of data could be done at the gateway or on the sensor/device itself?
That’s what Fog computing or Edge computing is all about. Let’s take for example a security camera which in its usual state captures data continuous and send them to the cloud to be processed for any abnormality. With the advent of edge computing, it would be able to process the video by its own and send the data to the cloud only when it detects any abnormality.
“Pegged at just under $80mn in 2017, the edge computing market in the US alone is projected to soar to more than $1bn by 2025”
The choice of the connectivity technology for your IoT application would solely depend on your use case. Trade off among power consumption, range, bandwidth, security and cost is inevitable as none of the existing technology promises to have it all.
It must be noted that even in case of wireless, at some point a wired network comes into the picture. Thus, the most commonly used networks for IoT applications are hybrid.
With the advent of Edge computing, will this discussion on the best connectivity technology become obsolete? Only time will tell…