Mobile IoT devices and connected vehicles transfer 10x more data at 40-60% lower cost by using millions of existing Wi-Fi hotspots

André Cardote, Daniel Moura, João Barros, March 2021

CONTEXT

As the number of mobile IoT devices continues to grow dramatically worldwide, including connected vehicles, telematics units, dashcams and industrial handhelds, so does the massive volume of data they transfer to and from their backend. Even with the advent of 5G, cellular networks are not ready to face this data tsunami of machine-to-machine (M2M) communication with very different requirements from typical smartphone subscribers. Networks do not scale and companies are forced to limit their data, AI capabilities, and services. In this white paper, we look into how Wi-Fi technology, often called the hidden champion of mobile connectivity, is capable today of offloading petabytes of IoT data using Veniam’s intelligent networking platform.

WI-FI TECHNOLOGY HAS THRIVED FOR MORE THAN 20 YEARS

The IEEE 802.11a/b standards were published in 1999 and became the first widely adopted Wireless LAN standards. Wi-Fi has undergone 6 Generations so far, which although differing in operating principles are all backwards compatible. Initially thought for stationary scenarios, Wi-Fi has evolved over time, as new radio designs and new standards brought improvements to the ability of devices to connect on the move. Wi-Fi operates in the 2.4 GHz, 5 GHz and 6 GHz unlicensed spectrum bands, which means anyone can operate a Wi-Fi network without having to pay for a spectrum license.

WI-FI IS AVAILABLE WORLDWIDE TODAY

Today, Wi-Fi is the most commonly used wireless communications technology. 60% of all the mobile phone data flows through Wi-Fi, and over 3 billion Wi-Fi enabled devices are shipped yearly. By the end of 2021, there will be 22.2 billion devices in the market, out of which 542 million are Wi-Fi hotspots (Figure 1), according to Statista (2021). In November 2020, Wi-Fi averaged worldwide download speeds of 91.96 Mb/s and upload speeds of 49.44 Mb/s compared to 45.69 Mb/s, and 12.60 Mb/s for Cellular broadband technologies (Ookla, 2020).

Many telecom operators and cable companies worldwide have made the move to offer community Wi-Fi networks by installing Wi-Fi infrastructure in busy streets and, more importantly, by turning peoples home Wi-Fi routers into public Wi-Fi hotspots. The basic principle is that every subscriber at home gets a private channel that they can use and a public channel that other authorized users can access with the right Wi-Fi credentials. This makes Wi-Fi widely available at road level, in public spaces and residential areas.

Surprisingly, these community Wi-Fi networks are largely underutilized, mostly because smartphone users often prefer to use their cell data plan rather than to stop what they are doing to go through the burden of Wi-Fi connection and authentication.

Figure 1. Density of Wi-Fi networks around the world. (Wigle.net, 2021)

In contrast, Mobile IoT devices, such as Wi-Fi enabled dashcams, telematics units and industrial handheld devices, can deal with intermittent Wi-Fi connection and authentication automatically within a few seconds. Since much of their data is delay tolerant, mobile IoT devices and their applications can make the most of Wi-Fi networks even if they only get to use it for a few seconds on the move. What is most important is that during those few seconds, they transfer valuable chunks of data that can be reassembled in the cloud. The end result is large volumes of data that add up and are offloaded successfully away from congested and much more expensive cellular networks.

WHAT IT LOOKS LIKE IN THE FIELD

Today, mobile IoT devices powered by Veniam are connected to Wi-Fi 25% to 50% of the time (Figure 2). This is possible by using the Veniam Platform to leverage the Wi-Fi infrastructure of multiple Wi-Fi network providers that together enable devices to transfer up to 2 GB/hour on the move. Devices connect to Wi-Fi every 20 seconds on average, enabling Wi-Fi to support both delay-tolerant and near real-time data transfers.

Figure 2. Percentage of time connected to Wi-Fi in urban and suburban areas in the US, Japan and Germany.

Connectivity patterns in urban and suburban centers

The time mobile devices are connected to access points, and the amount of data they transfer, is largely influenced by their activity. Since mobile IoT devices are moving most of the time, it is no surprise that in urban and sub-urban centers most of the connections have up to 10 seconds (Figure 3). Looking at a sample of 1000+ connections in Philadelphia, US, we see that over 30% of the connections last 5 to 10 seconds. It is interesting that connections with 5-10 seconds and 40-45 seconds equally contribute to the total uploaded data. This shows that both short and long connections are important contributors to the amount of data sent through Wi-Fi.

Figure 3. Histogram of connection duration and contribution of connections to the amount of data sent over Wi-Fi.

Taking advantage of both short and long connections requires an adaptive system that makes connection decisions depending on the device state. Veniam’s software adjusts dynamically to the mobility of the device, allowing for higher data rates when it is stopped, or lower connection setup times when it is moving, for instance.

Network capacity for mobile IoT devices

Typical internet users need a larger download pipe than upload. Their main use cases for connectivity are often streaming large amounts of data into their devices or browsing the web. In contrast, IoT devices have a different problem to solve: they generate data (e.g. from sensors) that needs to be uploaded to the Cloud. Even if each single device only needs to upload a few megabytes of data per hour, thousands of devices uploading data makes for significant volumes of data. Frequently, that data is delay-tolerant, that is they can wait a few minutes, hours or even days to have the data available in the Cloud. Today however mobile IoT devices seldom take advantage of that to send data over the most cost-effective network.

To determine how much data Veniam-enabled devices can upload via Wi-Fi on the move, we ran field campaigns in various urban and suburban centers. The results were around the 425 MB/hour mark in most locations, reaching 1.3 GB/hour in Philadelphia, US (Figure 4). This means that a mobile IoT device on the move 25 hours/week has the capacity to upload about 45 GB/month. This can go up to 3 times higher depending on the location.

Figure 4. Wi-Fi capacity (upload and download directions) in urban and suburban centers in the United States, Japan and Germany.

For some mobile IoT devices, download capacity is equally important. That is the case of advertising screens or video-on-demand in taxis, among others. Download capacity is always higher in the downstream direction, going up to 1.9 GB/hour in Jersey City, US.

Travelling between cities

Some vehicle-mounted devices, for instance, spend considerable time travelling between cities. To determine the capacity of existing networks in this scenario, we collected 21 hours of data from Veniam-powered devices in vehicles traveling in commute routes in Germany. These vehicles commuted through countryside roads of suburban and rural areas in three different regions (Figure 4).

Figure 4. Countryside route between Wolfsburg and Brunswick in Germany.

On average, the devices are connected 24% of the time, uploading 210MB/hour and downloading 266MB/hour. This translates into 23 to 29 GB/month of data for devices on the move 25 hours/week, which proves that there is Wi-Fi capacity available even outside city centers.

HOW VENIAM MAKES IT VERY SIMPLE TO LEVERAGE WI-FI

To reap the benefits Wi-Fi, mobile IoT device operators need:

1. Embedded software to manage all networking and data aspects on the device.
2. Cloud services to manage all networking and data policies and configurations remotely.
3. A worldwide network of Wi-Fi partners to provide secure access to the Wi-Fi networks.

CONCLUSION

Veniam’s Mobile Wi-Fi Offload offers all of the above, so that mobile IoT device operators can focus on their core business and trust that their data will be in their backend when they need it while keeping the connectivity costs under control.

Wi-Fi is available worldwide today and has excess capacity to handle large amounts of data from mobile IoT devices. With Veniam’s Mobile Wi-Fi Offload service, mobile IoT device operators can use this excess capacity to transfer their data in a cost effective, seamless manner, while freeing their attention to focus on their core business.