Embedded Systems Communication – SY0-601 CompTIA Security+ : 2.6

Embedded systems can use many different methods for communication. In this video, you’ll learn how embedded systems use 5G, narrowband, baseband, and Zigbee networks.

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With the increasing number of embedded systems that are being deployed, it’s important to know how these devices communicate to each other. So in this video, we’ll look at the methods for embedded system communication.

The fifth generation of cellular communication is 5G, and it’s a technology that was introduced in 2020 to be able to provide high-speed communication over wireless networks. 5G communication can use very high frequencies to be able to get speeds that are upwards to 10 gigabits per second. Many of the more common connections will probably be around 100 to 900 megabits per second, but that is still a significant throughput that can be used over these wireless cellular networks.

These are going to have a dramatic impact on the capabilities of our internet, of things devices, these will have large amounts of bandwidth available to these devices, you’ll be able to transfer larger amounts of data, there will be faster networking and notification of these devices, and there will be the ability to send more information into the cloud, hopefully, to provide even more processing functionality, using these high speed 5G networks.

To connect over one of these cellular networks, you need to have a Subscriber Identity Module or what we commonly call a SIM card. This is a universal standard for an integrated circuit card, and it’s common to see these in our mobile phones. But of course, if you have internet of things devices that will be using these 5G networks, then they’ll also need a Sim card inside of those IoT devices.

These SIM cards provide that important connection, between the internet of things device, and the cellular network. These will often contain an IMSI. This is an International Mobile Subscriber Identity value. This allows the mobile network provider to be able to recognize this SIM card and be able to add it to the cellular network. This might also contain authentication details, contact information, and other important information about the IoT device.

If you’re managing a large number of IoT devices that are connected over a cellular network, then you’re probably going to be responsible for managing all of the SIM cards that are connected to those IoT devices.

If the embedded device is not using the cellular network to communicate, then it may be using frequencies over a narrowband connection. This is allowing communication across a very narrow range of frequencies, and it’s very common to be able to send this communication over these bands, across a very long distance.

As you can see by this picture, this narrowband signal, uses a smaller amount of the frequency bandwidth, than a broadband signal might allowing you to have many different communications in a single set of frequencies, and very often this can communicate over much longer distances.

You might find this narrowband communication, where there is SCADA equipment, or sensors, that are in oil fields, and these sensors may be distributed across a very large geographical distance.

If broadband is using a large number of frequencies to be able to communicate, then a baseband is using a single frequency to be able to communicate. This is very often done over a single cable or a single fiber connection, and it’s usually using a digital communication. Since there is a single frequency being used for this communication, anything going over this link is going to use all of the bandwidth on that connection.

This can support bidirectional communication, although the communication is usually going one way or the other, over a particular fiber, or copper connection. It’s very common to see baseband being used on our wired ethernet connections. For example, the 100 megabit, 100BASE-TX, the gigabit, 1,000BASE-T, and the 10 gig, 10GBASE-T, are all ethernet standards using baseband, and the term, base, in the name is referring directly to that baseband communication.

But you may notice that your internet of things devices in your home are not connecting using a wire, they’re communicating over wireless networks. And they are very commonly using a standard called Zigbee. This is an IEEE standard, specifically standard, 802.15.4 Personal Area Network, and you can see based on that name, why we call it Zigbee.

This is an alternative to WiFi, it’s different than Bluetooth, it’s a way to communicate with all of these IoT devices, over longer distances, using less power. This also allows all of your IoT devices to create a mesh network. This means that devices on one end of the home can hop through other IoT devices to communicate with your management stations, that might be on the other side of your home.

This means if you’re changing the temperature of your air conditioning controls, or you’re modifying the lighting on these IoT devices, it’s eventually communicating through the Zigbee network, to be able to control that device.

In the United States, Zigbee communicates over the ISM band. This is the Industrial, Scientific, and Medical band, and there are frequencies in the 900 megahertz and 2.4 GHz frequencies that are used by Zigbee. This means that you can have all of these IoT devices meshed together and use this wireless communication, without any special licensing required to be able to communicate, on these frequencies.