By 2020, Gartner predicts that 20.8 billion connected things will be in use worldwide, across consumer and enterprise markets. With this rapid growth in connected devices, data will need to be shared and accessed wirelessly between various wearables, smart sensors and other devices, in the most secure and effective manner.
This month, the Wi-Fi Alliance announced the IEEE 802.11ah standard, which was developed specifically for IoT devices. The technology will be formally called Wi-Fi HaLow (pronounced halo). Wi-Fi HaLow is a stripped back, low energy version of Wi-Fi, built to allow smart devices and sensors to communicate data to the Cloud.
With a variety of alternative ways for connected devices and sensors to communicate, including via Bluetooth 4.2, Sigfox, and LTE, this blog will explore what HaLow brings to the table and how it compares with the other channels, already available.
Working differently to the Wi-Fi we know and use already, HaLow operates at a much lower, unlicensed frequency, meaning that anyone can use it without having to pay for a license fee; much like Bluetooth. At such a frequency (900MHz band), this helps to:
- Cut down power consumption
- Extend transmission range
- Increase its ability to transmit in the presence of other interferences
- Transmit data through various barriers, such as walls or floors
Using Wi-Fi HaLow, it is expected that data can reach distances which are at least twice as far as modern Wi-Fi standards, if not more. However, due to the low frequency, Wi-Fi HaLow won’t be able to handle vast amounts of data. The Wi-Fi Alliance estimates data rates of between 150 kilobits per second, and 18 megabits per second. In other words, this will allow connected devices to send and received small pockets of data to and from the Cloud; not to stream high quality content.
Wi-Fi HaLow was primarily designed to allow devices to send data to the Cloud, at long distances and/or in challenging environments, using lower power than Wi-Fi or even Bluetooth.
Following the moves of the Bluetooth SIG with Bluetooth 4.2, it’s highly likely that Wi-Fi HaLow was developed as an alternative, competing technology for the backbone of the IoT. Where Wi-Fi HaLow has the potential upper hand, however, is range. Due to it’s use of the 900MHz band, HaLow will enable a stronger connection, that has better ability to penetrate walls, making it a better option for many industrial or enterprise IoT use cases.
Although announced a couple of weeks ago, Wi-Fi HaLow will not be available for use until 2018 where certification work will begin, according to the Wi-Fi Alliance. In the meantime, we are expecting to see Wi-Fi HaLow enables hardware to being produced in preparation for its official release. This also means that current routers and smart devices won’t be compatible with Wi-Fi HaLow.
It could well be that by the time Wi-Fi HaLow gets released, Bluetooth will have advanced further than HaLow. However, there is the potential that HaLow’s use of the 900MHz band, opposed to the 2.4GHz band used by Bluetooth, will be better suited for longer range use cases, especially ones that can penetrate through walls, with greater ease. In terms of range, we can expect Wi-Fi HaLow to reach at least 500 meters, in case of the 802.11n, or up to one kilometer (or further with the use of repeaters).
Wi-Fi HaLow, therefore is competing with Bluetooth and cellular data connections. Whilst it may not actually replace either (as each of the three has distinct advantages and both Bluetooth and Cellular are far more ubiquitous), it is an interesting development.
To really understand the value of each access method is to understand the unique use cases that apply to each of the technologies. Whether it be Bluetooth, Wi-Fi HaLow or Sigfox, companies need to focus on the needs and the pain points they want to overcome and find the technology that suits that case.