Mobile Device Connections – CompTIA A+ 220-901 – 3.5

There are many different ways to connect our mobile devices to each other and to other devices. In this video, you’ll learn about near field communication, mobile interfaces, tethering, and much more.

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One increasingly popular type of mobile device communication is NFC. It stands for Near Field Communication. It allows your mobile device to send small amounts of data over a limited area. It’s built into your phone or mobile device. You can use this for payment systems, you can use it for access to transportation, or you may use it to exchange information between two mobile devices. You can also use NFC for something like an access token, to be able to open doors, or identify who you are. If the NFC in your phone supports encryption, it becomes a very secure way to provide that access.

Early on, our mobile phones had many different kinds of cables. There was one cable for power, and you would use a completely different cable to be able to transfer data in and out of that telephone. Every manufacturer had a completely different cable for power and a completely different cable for data. Because of the challenges associated with having exactly the right cable for exactly the right phone, the European Union set down some standards for these power connections, so that there would be a single standard throughout all of Europe.

The standardization was hopefully going to be able to avoid scenes like this, where you might be in an airport and you’d have these devices that had all kinds of power connections, for every possible phone. Whether it’s an iPhone, or a Nokia, or another type of Nokia, or a third type of Nokia, or another fourth type of Nokia, or even a fifth type of Nokia, all using different power connectors from the same manufacturer’s phone. If you were able to take a single standard from this, that everyone could use, it would greatly simplify power on our mobile devices.

The European Union standardized on a USB interface, and specifically, the Micro-B USB interface. This Micro-B plug became the standard throughout Europe, and because of that, it’s now the standard that we commonly see in the rest of the world. If you have an older mobile device, it might still be using USB, but perhaps it might be using this slightly larger Mini USB plug.

Apple decided not to use the Micro USB standard for their devices. Instead, they use a lightning connector. This is proprietary to Apple. It sends eight pins on the end of the lightning display to send digital signals to iPhones, iPads, and iPod devices made by Apple. These lightening connectors provided Apple with some advantages over the Micro USB, specifically, they were able to output a higher amount of power over these lightning connectors. And they can be inserted either way for convenience. It’s a simpler design, and it’s a bit more durable than the Micro-USB interface.

Our mobile devices can also communicate without wires, using Bluetooth. Bluetooth is what we call a Personal Area Network because it sends information within a short area. And Bluetooth allows us to send large amounts of data over this Personal Area Network. We can connect up our smartwatches, we can put headsets on to hear and send audio, or connect up other devices to transfer information between our mobile device and these external devices.

Some of our older laptops and printers would use infrared to be able to perform file transfers or to do printing. But these days, we have a new resurgence of infrared that’s built into our smartphones. These are not used for file transfers and printing, but instead we can use them to control other infrared devices. It’s very common to see this at home when you’re sitting on your couch, and you can now control your television and other media devices using your smartphone instead of the traditional remote control.

One nice feature of many smartphones is the ability to turn your phone into a mobile hotspot. This is called tethering, where I can have my phone act as an 802.11 Wireless Access Point, and all of my devices can use my phone as the central communication point to the internet. This becomes useful if you have a tablet or other devices that wouldn’t normally have internet access, but they do have 802.11 functionality.

This allows me to use the 802.11 wireless functionality on my tablet to communicate to my phone, and my phone will then connect to the internet through the normal cellular network. The ability to turn your phone into a hotspot and provide this tethering may be specific to the type of hardware you’re using, or the services available on your mobile provider. There might also be additional charges associated with this, so you’ll need to check with your mobile provider to see what options might be available for you.