Release 13 of the 3GPP’s mobile broadband standard introduced two new categories of narrowband cellular technologies suited for IoT devices: LTE Cat M1 and LTE Cat NB1. They are subsets of two top-level standards: LTE-M and NB-IoT. They’re relatively new, but are already being heavily rolled out around the world. As of March 2019, they’re in 53 countries, supported by 104 operators, and are on their way to 16 more countries at present. They represent the beginning motions of what is soon to be a massive wave of low-bandwidth smart IoT devices slated to appear around the world. Everything from clothing to appliances to city infrastructure is soon to have embedded, intelligent wireless devices built in, taking advantage of the information around us in exciting and innovative ways.
Still, the question remains: Why two categories? eMTC (a subset of LTE-M) and NB-IoT were both introduced simultaneously in Release 13. While both categories are designed for mobile cellular devices with IoT applications in mind, they are quite different. If you’re planning on entering the IoT marketplace, it’s important to understand the difference between the two, and to select the protocol and hardware that supports your device’s needs.