The trend to support a diversity of connectivity under a common platform is not confined to wireless broadband. As the Internet of Things (IoT) gathers pace, there will be far greater demand for machine-to-machine (M2M) connections, many of them wireless. These will have even greater varieties of performance requirements, reflecting the vast number of different use cases that may emerge under the umbrella of IoT.
No single technology will address all these requirements, and there is a long list of wireless IoT protocols. This is likely to consolidate over time, but there will certainly be a need for at least one open, standardized technology for several key IoT profiles. These profiles vary by the degree to which they support:
- Ultra-low-power vs moderate power
- Long-range vs local range vs very short range
- Low data rate vs moderate data rate
- Ultra-low latency vs low latency
- Critical availability vs standard availability
- Unlicensed vs licensed spectrum
(Note: Some proprietary protocols are likely to continue to be used in specialist environments like public safety or railways.)
WiFi has the advantage of addressing a very wide variety of profiles because of the proliferation of its family of standards. This means it will play a role in most IoT environments, alone or interworking with more specialized protocols, or with cellular. Some IoT applications, such as vehicular services, or video-based apps like connected security cameras, will need the bandwidth of the wireless broadband network, implemented to enable other requirements like low latency (In critical environments this may take place in a private network or slice).
WiFi is uniquely placed to support broadband and narrowband IoT applications from a common platform that can work at varying levels of power consumption and signal range. The next release of 5G standards, Release 16, will prioritize IoT-focused capabilities such as latency below four milliseconds and very high availability, to support emerging cases in the URLLC (ultra-reliable low latency communications) category.
Relative Positioning of Selected IoT-Focused Wireless Technologies by Capabilities
|WiFi 5 and 6||Moderate||Moderate to long||High||Low||Unlicensed|
|LTE Cat-M||Low||Moderate to long||Moderate||Low||Licensed|
|LTE Cat-IoT||Very low||Long||Low||Very low||Licensed|
|Sigfox||Very low||Long||Very low||Very low||Unlicensed|
|Bluetooth Low Energy||Very low||Short||Low||N/A||Unlicensed|
|802.15 – ZigBee, Thread, 6LoWPAN||Very low||Short||Low||N/A||Unlicensed|
Source: Maravedis and Rethink Research
Low power wide area network (LPWAN) connections are a particularly interesting example of the need for multiple technologies for IoT, potentially with WiFi, the most ubiquitously installed in networks and devices, as a unifying link. This is the main area, along with the well-established WPAN standards, where there are non-WiFi technologies operating at scale in an unlicensed spectrum. WiFi and LoRaWAN are two of the most adopted unlicensed technologies and together they address a large proportion of IoT use cases. The approaches for these technologies are disrupting private-public business models and also enabling participation in 5G success. The WBA and the LoRa Alliance have published a joint white paper to demonstrate how these two widely deployed IoT Connectivity technologies can be utilized in tandem to effectively support a vast array of use cases.
LPWAN will support applications such as intelligent transportation, smart lighting and asset tracking, to name a few examples. LPWAN provides a good example of how multiple unlicensed and licensed spectrum technologies will coexist. HaLOW, the brand name for the 802.11ah standard, allows WiFi to be deployed in the sub-GHz unlicensed spectrum to support LPWAN use cases. Other unlicensed spectrum options include LoRa and Sigfox, while there are two LTE-based choices for licensed bands, LTE Cat-M and LTE Cat-IoT. Each of these technologies supports a different balance between power consumption and data rates, making them optimal for different applications.
Many service providers are already deploying two or more of these technologies in tandem to support the wide diversity of services that will make up IoT. For instance, in a complex environment like a smart city, being able to use a combination of connectivity technologies to support use cases with different requirements and integrate them all under a common management platform will be key to an economically viable and richly functional solution.
While it is important to have a diversity of technologies to support the widely varying requirements of IoT, it is also essential that these technologies can interoperate seamlessly to avoid creating islands of communication, as these would severely restrict the ability to create a broad platform in which different applications can exchange data easily.
This article first appeared on IoT for All