Communication with IoT devices
One of the biggest problem of the IoT world is to choose one appropriate way how to get data from/to your device. Few years ago, we could use mostly GSM networks, which is expensive and power consuming (and that is a problem for devices powered on batteries). Let’s see what options we have now. You will find a comparison table at the end of the article.
Wi-Fi
Standard way of connecting device to the Internet. Cheap, always available in cities, average power consumption. Thanks to the boom of ESP8266 and ESP32 chips Wi-Fi became available to broad variety of makers, programmers and corporations. Thanks to various libraries can literally everyone make weather station communicating with the Internet easily.
GSM
GSM is available in areas, where no Wi-Fi is available. In some countries the price for data and SMS is very nice. The problem is that GSM modules are power consuming and it is not always easy to get on with them easily. On the other hand, possibility to send data AND sms can be used to our advantage. If destination server (on which we are sending data from our device) is not responding, we can always (and immediately) use sms message as a backup.
Sigfox
Sigfox is a company founded in 2009 in France with the intention to build wireless network for low-power devices like sensors and electricity emters. Sigfox offers robust backend for managing devices and messages. Every device can send up to 140 messages per day (why?). Sending out a message requires circa 49mA. The biggest problem is that every device requires to be “sigfox certified” before being sold on the market. Requires a contract with local provider/reseller (like SimpleCell in Czech republic).
LoRa
“Long range, low power wireless platform”. New technology for IoT devices. Secure, partially open (everyone can build a receiving station) and low power. Similar to Sigfox with two disadvantages – not so long range and there is no “one official network”. This could be interesting for local sensors – smart homes, factories, etc.
Comparison
| Name | Range | Pricing | Transmitting power | Contract required |
|---|---|---|---|---|
| Wi-Fi | small | can be free | quite high | usually no |
| GSM | almost everywhere | average | high | preferred |
| Sigfox | large cover in some countries | quite high | low | yes |
| LoRa | depends on location | depends on local network | quite low | depends on local network |
Do you use any other type of communication? Please share in comment, so I can extend the article.
