When it comes to choosing the technology stack for IoT network, perhaps the major choices available with the developer are — Cellular (GSM/LTE) or WiFi. However, there are several other choices for consideration — Bluetooth, ZigBee, Active RFID, loWPAN, EtherCAT, RFID to name a few.
Given each technology’s characteristics on bandwidth, cost, coverage, and security, which one is the best for Appliances and Consumer Electronics (ACE) sector — cellular, Wi-Fi or both? Let’s checkout.
Bandwidth
For years, WiFi had a significant advantage in bandwidth over cellular, with older 802.11bgn WiFi technologies offering speeds up to 450 Mbps and the newer 802.11ac Wi-Fi technology offering speed up to 1.3 Gbps. Moving forward, with 4G, cellular technology has also become as fast as 1 Gbps, making it comparable with WiFi. As 5G rolls out, we can expect it to drive innovation in IoT space.
Conclusion: Both are almost comparable in terms of bandwidth.
Cost
Embedded GSM modules are almost 3 times the cost of a WiFi module. Apart from hardware, with the cellular network, there will be a bill to cough up every month, while WiFi has strong established base in most households, there will be no additional costs to connect multiple devices.
Statistics: The internet on WiFi is about 2 paise per MB and about 23 paise per MB on Mobile Data. (Source: TRAI consultation paper)
Conclusion: WiFi is far more cost effective than Cellular
Coverage
Wi-Fi is a LAN (local area network) which provides excellent coverage in a limited area (home/office etc.). The moment, a connected device leaves that area, connectivity is lost. On the other hand, cellular data coverage today is extensive and growing, as wireless network operators compete with each other to offer better coverage to their customers.
Statistics: From TRAI report of May 2018
Total Fixed (Wire and Wireless) internet subscribers — 21.73 million
Conclusion: As appliances and consumer electronics goods usage is generally confined to the same location, WiFi gets an edge over Cellular for its better bandwidth.
Security
No network is 100% secure. Nonetheless, cellular does possess some security advantages over Wi-Fi. The cellular data is encrypted by default between Mobile device and telecom base station. However, the data has to be encrypted manually at the application layer. While Wi-Fi data has to be encrypted manually from stage one. Manual encryption introduces human error into the security equation, and as seen in recent cybersecurity attacks, such human-error related vulnerabilities can and will be exploited by cybercriminals.
Conclusion: WiFi and cellular both have data which has to be encrypted at the development stage to ensure data is always secured in transit.
However, with cellular increasingly becoming equal to or better than Wi-Fi in terms of bandwidth, cost, coverage and security, many developers who previously might have considered WiFi as their only option for IoT applications are likely to be looking at, if not switching to, cellular over the coming years.
