In the fast-paced world of IoT communications, it can be difficult to get a clear picture of what’s new, what is no longer relevant, and just how far network technology has come. For a long time, 2G satisfied all the desires of machine-to-machine communications, with a low transfer rate, enough power to send larger packets, and limited interference from other devices.
This all changed once smartphones came along, leading operators to open higher-capacity bandwidth to satisfy huge demand. The IoT will precipitate a similar influx of low-energy traffic, but most carriers are still focused on consumers – in the US, AT&T, Verizon, and T-mobile have all announced closure of their 2G bands. Telenor Norway and Vodafone on the other hand will continue to support 2G for now, even if that means sacrificing 3G.
What’s next for IoT communications?
Low-power wide-area networks (LPWANs) have sprung up in recent years, offering extremely low transfer rates specifically for IoT communications (Sigfox processes packets up to 12 bytes – about 10% of an SMS message). These networks – LoRa, Sigfox, and Ingenu to name a few – operate on the unlicensed sub-GHz spectrum, which is busy in the US and Europe, and fractured in other regions. This means it may be a while before LPWANs can support IoT communications on an industrial scale, but they are expanding globally nonetheless.
Of course many IoT devices - security cameras, wearable devices - need more speed than 2G or LPWAN can provide. This is where LTE’s efficient use of spectrum comes in, making it more than just a fast version of 3G. LTE uses all of its bandwidth by hosting different technologies that fit between other communications, or use the ‘guard bands’ at the edges to straddle the licensed/unlicensed boundary.
The leading cellular low-power technologies are NB-IoT and LTE-M (or Cat-M), with NB-IoT favoring much lower energy devices. Unfortunately, NB-IoT does not use the LTE band, and is therefore more difficult and costly to set up. Cat-M caps its bandwidth to only 1.4MHz, so it doesn’t interfere with consumer traffic, and uses existing LTE infrastructure – a huge benefit to users with a large fleet of devices, especially in hard-to-reach areas.
What’s best for me?
The IoT is filled with applications of all sizes, power requirements, and data consumptions, so the answer to ‘which one is best’ depends on your needs. Pod is an agnostic connectivity provider, so we’ll help you find the best fit for your business, without pushing one network technology over another.
The vast majority of IoT modules are getting smaller and more specialized and require much less data for each data transaction. NB-IoT or LPWAN may seem the best choice, but with limited infrastructure these technologies will struggle to support roaming applications, and require a large investment to set up.
Cat-M offers the best cellular alternative, because users can deploy it without any additional cost or effort, and can also avoid switching to 3G and then again to LTE later. IoT companies should consult an IoT expert before making any decisions, but one thing is for certain: IoT-specific connectivity is changing the game, and Cat-M is leading the charge for the cellular networks.