As with every new technology trend, there are always standards that compete with each other trying to solve the new problems encountered by the technology needs. Back in 2010 when the mobile world was nascent, we had Mobile OS Inflation. Clever technologies, as we pointed out in Episode 1, are no exception. In fact one could argue that IoT has broken the record of protocol standards. As Nordic recently posted on their Get Connected Blog: “from ANT to Zigbee”.
The challenge with “things” is that they have very different needs that will drive different connectivity standards. Wireless standards are typically designed to optimize battery life while maximizing performance for the specific application they are designed for. They key performance attributes that IoT devices are typically concerned about are: range, data rates, frequency of data transfers, latency, security, and reliability. The “goldilocks” of these requirements are clearly different for different applications.
Let’s look at a few examples:
- A self-driving car will need long range, high and frequent data rates with low latency but it benefits from large power source. The network needs to be secure and very reliable.
- A remote thermometer will need long range but low rates and infrequent data transmissions. High latency is acceptable, but battery availability may be limited.
- A beacon will need to be really small, thus driving a very limited battery capacity, but its data needs are also limited. Depending on the application, the range needs can also be short.
- A switch needs very low latency, but very infrequent and low data rates, while power is not an issue since they benefit from being hardwired.
These examples make the point that one wireless standard will not be sufficient for optimal operation of all of them. So the need for various protocols is real.
Ant+, Bluetooth, Zigbee, and Z-wave are very similar in nature but do differ in terms of performance attributes. Ant+ (owned by Garmin) has been primarily focused on fitness devices like heart rate monitors, cycle computers, etc. Bluetooth is perhaps the most ubiquitous. It is present in every smartphone, tablet, and computer originally as a low range low data rate communications protocol. However, recently with the additions of BLE and Bluetooth 3, it is expanding into many more IoT use cases than it was before. Zigbee is arguably the IIoT (industrial IoT) protocol of choice. It has been available before IoT was even a thing (no pun intended). It is a very mature protocol. Extensions like Zigbee Pro and Zigbee Remote Control give it flexibility with reliability, security, and scalability for very complex systems. Z-Wave, relatively new to the party, is a very low latency and low data rate protocol that supports meshing, making it ideal for home automation projects that include lights, valves, sensors, and the like, where nearly instantaneous action is expected.
WiFi, of course is everywhere and growing. Newer variants can support rates up to 1 Gbps. Chipsets are very power efficient, scalable, and extremely cost effective these days. It is mostly a communications network protocol, but due to its omnipresence, there are a lot of IoT devices out there based solely on WiFi.
For long range needs there is also a growing collection of protocols for IoT applications like Thread, Sigfox, Neul, or LoRaWAN. There is a version of Cellular IoT that 5G technologies promise to make widely available. It has high data rates and capacity with extremely low latency.
The big question is what technology to use for IoT projects. The truth is that it is not possible to settle on a single one even for a simple smart home project. We have launched applications that combine several of these in order to have the best possible outcome.
It is unlikely that a single protocol will win the IoT battle. We can expect extensions to some of the most common ones to make them more suitable for different use cases. Some protocols may wind up relegated to niches and some may even vanish in the future. However, we will have to live with protocol inflation given the diverse nature of IoT needs. Successful installations will focus on the right choice of devices and protocols optimized for each part of the project rather than a choice of standards to make it easier for the installer. Remember, it is about the best performance of the application, not about technology choices.