How does wireless broadband (Mi-Fi) work?

How does wireless broadband (Mi-Fi) work?

Tom Paton - Broadband Savvy

Tom Paton | Broadband Savvy

Mobile Wi-Fi (also known as MiFi) is a way to get online and create a Wi-Fi hotspot that doesn’t involve using a traditional home broadband connection. In this guide we explain how MiFi works, and compare it to traditional broadband.

Rather than using fibre or copper cabling to connect to the internet, MiFi devices use the 4G or 5G network to get online, just like your phone. And rather than plugging into a power point, MiFi devices are battery-powered, meaning they are very portable, and can be used when travelling.

In this guide, we’ve explained how MiFi works, and compared it to traditional broadband. We’ve also explained some of the pros and cons of using MiFi to get online.

How MiFi works

To get online using MiFi, you’ll need to buy a MiFi device and data plan from a mobile carrier. We’ve discussed how this works in more detail in the next section.

Once your device comes in the mail, you’ll need to set it up.

  • First, pop the back cover off the MiFi device. There is normally a gap in the corner you can lift up the cover from.
  • Then, insert the SIM card. There might be a slot for the SIM that you’ll need to push it into, or there might be a cover that you’ll need to lift up. In the shipment you received, you will likely receive a small card, about the size of a credit card, which you need to push the SIM card out of. Ensure to push out the right size SIM from the card, otherwise it won’t fit in the device. Normally, it’s the smallest “Nano” SIM that you’ll need.
  • Insert the battery into the MiFi device, and put the cover back on. Note: sometimes the battery is integrated into the device, and this step isn’t necessary.
  • Hold down the power button for 3-5 seconds until the lights illuminate on the device. Your MiFi device will start up, which could take a few seconds, and you should see a signal light, which is normally green, once the device connects to the mobile network. If the device doesn’t power on, it might need charging, but normally the MiFi device will come with some charge out of the box.

At this stage, you’re ready to get online. You can connect to the MiFi device’s Wi-Fi hotspot using your phone, computer, tablet, or any other Wi-Fi-enabled device.

Normally, the Wi-Fi network password is printed on a label on the back of the MiFi device, or there might be a card with the login details included with the device.

Getting online with MiFi

When you get online using MiFi, the device will connect you to the internet using the 4G or 5G network. In most cases, the device will use 4G rather than 5G. There are some 5G MiFi devices on the market at the moment, but they aren’t commonplace, and are quite expensive to buy.

To use the internet on your MiFi device, you will need to have a constant connection to the mobile network. You can use your MiFi device when travelling, as long as you get signal. It’s important to note though, if you go overseas, you will likely need to enable roaming before you travel, and roaming charges may apply, depending on the mobile carrier you’re using.

Your mobile broadband connectivity can vary considerably depending on where exactly you position the MiFi device. If you plan to use mobile Wi-Fi at home, it’s a good idea to test the device in different parts of the house, to see where you get the best speeds – you can use a website like to measure your speeds in different locations.

You will also need to consider the position of the devices you plan to get online with, relative to the position of your MiFi device. It’s all well and good to put the MiFi device in the corner of your house that gets the best 4G signal, but if your computer is on the other side of the property, you might not get a very good Wi-Fi signal, resulting in dropouts, or slow download speeds.

Buying a MiFi device

Normally, the MiFi device and data plan are sold as a bundle. You’ll need to choose:

  • Which mobile network to use – it’s a good idea to check the network coverage map of a few different companies, to see which one offers the best signal at your address. You should also compare networks based on their pricing, because some are significantly cheaper than others.
  • The MiFi device you’d like – at the moment, most mobile networks sell 4G MiFi devices made by Huawei or ZTE, which are all quite similar in terms of battery capacity, Wi-Fi performance, and ease of use. However, there are some networks that now offer 5G MiFi, for a higher monthly cost.
  • How much data you need each month – you can buy MiFi devices with anything from a 4 gigabyte (GB) monthly data allowance, all the  way up to unlimited data usage. If you plan to use MiFi for lots of data-intensive activities, such as watching videos, or downloading large files, it’s a good idea to pay more for a higher data limit.
  • What contract length you want – typically, you will have the choice of a 12, 18, or 24 month contract. Month to month MiFi plans are also available, although they normally have a higher monthly cost.

You can read the Broadband Savvy MiFi guide to learn more about the different MiFi deals currently on offer, and the differences between the devices offered by each mobile network.

You can also buy a MiFi device on its own, and then pair it with a data plan that you’ve bought separately. Just ensure that the data SIM you’re using is not restricted to use with mobile phones, otherwise you won’t be able to use it in your MiFi device.

Advantages of MiFi

There are a number of advantages to using MiFi when compared to other ways of getting online:

  • MiFi devices are quite straightforward to set up, and are easy to use.
  • You don’t have to commit to a long-term contract if you don’t want to. Only a few home broadband providers, like Cuckoo, offer you the ability to join on a month-to-month agreement.
  • You can get online almost anywhere, as long as you get mobile network signal.

Disadvantages of MiFi

However, there are also a few disadvantages to using MiFi to get online.

  • Your latency (also known as “ping”) will be higher when using MiFi when compared to fixed-line broadband. This means that you’ll lag a lot more when playing online games.
  • You’ll normally have a data usage limit, unlike when using a traditional home broadband connection.
  • You will be restricted to 4G speeds, unless you pay more for a 5G MiFi device. This means that in most cases, your download and upload speeds will be slower than a traditional broadband connection.
  • The Wi-Fi hotspot created by a MiFi device typically won’t be as good as with a good wireless router. This means that your signal won’t be as good when positioned a long way from the device, and you’ll only be able to get online with 10 or so devices at once using MiFi. With most Wi-Fi routers, you can connect 64 or more devices to the network at the same time with no issues.

There you have it, there's Cuckoo's roundup of Mifi and its pros and cons in collaboration with Broadband Savvy .

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