What is the difference between LTE and Wi-Fi?
The key difference between LTE and WiFi is coverage. LTE coverage has been widely expanded in recent years, so there’s likely to be mobile coverage where you need it. Wi-Fi on the other hand, even if it is a public Wi-Fi network will have a limited footprint, when compared to LTE.
Let’s look in more detail how LTE and WiFi compare.
What is WiFi?
How Does WiFi Work?
WiFi depends on a critical central hub, or “access point” that propagates the WiFi network. This hub controls which WiFi devices can connect to the WiFi network it creates. It also brokers connection between devices on the WiFi network and controls the transfer of data between them. Many WiFi hubs are also a part of a broadband router that allows a WiFi device to reach the internet, and transfer data.
Extending a WiFi network’s coverage area can be done by adding further hubs. These can be linked together using either wired /ethernet connections, or WiFi. The capabilities of WiFi are constantly evolving, here's a good summary of what WiFi can do and how that has developed over time. .
What is LTE?
How Does LTE Work?
A mobile operator's phone masts generate the wireless network and allow LTE enabled devices to connect to it. The ability to connect depends on a SIM card on the device that initially “shakes hands” with the network and validates that it is allowed to connect.
Once connected, LTE provides the device with the ability to wirelessly connect to the internet. Unlike Wi-Fi, it does not allow direct data connectivity between devices connected to the same network. That has to be achieved via the internet. In that respect it breaks the conventions of a phone call on the same network, where direct calls between devices are the norm.
What are the differences between LTE and WiFi?
LTE has a major benefit in that you do not need to worry about managing the network. All you will need is your IoT device and a SIM. The mobile operator owns and manages the physical network needed to provide you with the connection to your device.
Unless you are using a public Wi-Fi network you will need to build and operate the network yourself. If you already have the network for other reasons that may be fine. However, the cost and time of using your own Wi-Fi network needs to be factored into your decision making.
The security of both your data and the devices you use should be a major concern when deploying your IoT solution. The security built into LTE networks, from user authentication to encryption of all traffic, is considered significant. It is constantly being evaluated and updated by cybersecurity experts. It should be remembered that to some extent the operators’ reputation depends on it.
By contrast, with WiFi, the security is outsourced to the user. There are many popular tools/protocols to deliver security on WiFi networks. However, they depend on the user to implement and manage them to deliver the promised benefits. You can read more about the risks and issues associated with WiFi networking (private and public).
Unless you are prepared to spend time setting up and managing the security you need to manage your data and devices LTE is a clear winner in this area.
WiFi will have a limited footprint, even if it is a public WiFi network when compared to LTE. The mobile operators have had a major drive to extend coverage in recent years to meet smartphone user demand. This means it is highly likely mobile coverage will be available where you need it. In addition, if your solution will be mobile, tracking a delivery vehicle, the breadth of coverage a LTE network offers will be key and so probably the best choice.
WiFi may well be suitable for a static solution, for example tracking temperature in a storeroom. If the storeroom is on-site, within the same WiFi network footprint as you, then it will be a good option.
Where the storeroom is at a remote location the number of sensors ay well determine the decision, and whether there is a broadband connection and existing WiFi. Where your IoT solution is static, in a remote location with no existing network connections, LTE could still be the best solution.
LTE and WiFi in an ever changing world
Mobile Operators are now focusing on LTE as the replacement for 2G services that they are now retiring at an increasing rate. Since this article was first written 2 of the 4 operators in the UK have announced they will be shutting their 2G networks down in 2025. This allows them to re-use the spectrum to provide much needed capacity for LTE services. LTE network architecture is also seen as the building block for the future of mobile as it was designed to be fully multimedia.
WiFi is also evolving to provide higher throughput and better security management. Next generation hubs are becoming widely available and the increased management capability means the gap between LTE and WiFi is closing fast. This means we are heading towards an environment where LTE and WiFi can work together seamlessly to provide the user with continuous connectivity removing any fear of missing out on that critical social media posting.