Miracast, the CWNA and the Wi-fi Alliance


As a veteran teaching CWNA (Certified Wireless Network Administrator) I cover many wireless innovations in my classes. One of the newer technologies addressed by the WiFi Alliance is Miracast. The Miracast certification program started in 2012 and it is now offered in Windows 10 and on Android phones. So what does it do? The cool thing about Miracast is that it lets you “wirelessly-connect” a computer display to a TV monitor and display at 1080p with 5.1 channel digital audio. It’s a wire free substitute for an HDMI cable. This is a great technology for anyone who gives presentations to any size audience. Instead of running a long cable across a table, or having your audience huddle around your computer, you can send the video display of your screen to a remote monitor. Let’s take a look at how this technology works.

The first thing to know about Miracast is that it uses the 2.4 GHz  ISM band to create the connection. It may move to the 5 GHz band once it initially connects, but in order to make the initial connection you need to have a radio card that operates in the 2.4 GHz band.

The next thing to know is that you don’t need to have a wireless connection to a network in order for it to work, but you could have a connection to a wireless network and a Miracast connection running at the same time. Miracast is built on the WiFi Direct technology, which is a point to point technology that is often used to connect printers or gaming devices to a network. WiFi Direct uses Push Button Control or PIN number generation to create a point to point connection between devices. Miracast adds a wireless display option in Windows 10.

In order to connect a TV display to your computer you are probably going to need a special dongle that has an HDMI connector and a USB connector. Most TVs do not have Miracast installed as of yet, so having the dongle will make sure that you can connect to any TV that has an HDMI port and a USB port available. I recommend the Microsoft Wireless Display Adapter that you can buy on Amazon for $48.95. It will take the guessing out of the equation.
Once you plug it in, go to the display options for your computer and look for the Wireless Display Settings. When you click on this link you are enabling Miracast on your computer and it will start scanning to find any Miracast enabled networks that are within range. Choose the Microsoft Wireless Display Adapter SSID and the connection process will begin.

When the connection is successful you will see your screen “mirrored” on your TV. This is different than Chromecast in that you can display anything from your computer to the TV monitor, whereas with Chromecast you are just enabling your computer or smartphone to stream video. Using Miracast works great for projecting PowerPoint presentations or any applications that you use on your laptop.  You can also use Miracast to display movies from Netflix, HULU, or any other service that you may want to display on a larger monitor, just like you can with Chromecast, but Miracast goes beyond that and allows you to display anything that is on your computer.

One final word about Miracast; it is highly susceptible to interference. Miracast initially connects to a 2.4 GHz stream, but then may change to the 5 GHz  band if it’s available. Sometimes, if I’m in a multi-tenant environment, I have a hard time connecting, but it will react favorably if I just move my laptop to a different position and try again. Miracast is currently on version 2 of the standard and the connectivity issues are much less now than they were in version 1. I highly recommend buying the dongle and giving Miracast a try.

Learn more about our CWNA classes now


Please enter your comment!
Please enter your name here