Miracast: a near-perfect wireless streaming solution

Streaming content from your mobile device to a TV has been a pretty painful affair to date, but the new Miracast protocol is set to straighten out sharing, making wireless connections simple.

Joseph Hanlon Special to CNET News
Joe capitalises on a life-long love of blinking lights and upbeat MIDI soundtracks covering the latest developments in smartphones and tablet computers. When not ruining his eyesight staring at small screens, Joe ruins his eyesight playing video games and watching movies.
Joseph Hanlon
3 min read

If you enjoy following the fast-moving world of smartphones and tablets, then you are going to start reading a lot more about Miracast over the next few months. But what is Miracast, and why do you want it?

Hit this Miracast shortcut on the LG Optimus G, and you are halfway to connecting your phone to the TV. (Credit: CNET Australia)

We'll get to the techy details in a moment, but the short version is that Miracast is the next logical step in the evolution of streaming from a mobile device to a large screen, like a flat-panel TV or a computer monitor.

So far, we've had technology that lets us "push content" from one device to another, notably DLNA. This style of solution allows you to select a file from one device and view it on another, but it is typically limited to multimedia files, like movies and photos. DLNA also tends to be fairly difficult to set up, requiring a common wireless network for both devices to have access to, passwords and dedicated apps.

We've also been able to connect devices to screens by using dedicated wired connections, like micro HDMI and Mobile High Definition Link (MHL). These solutions are more flexible content-wise, because once you are connected, you can see your device's display mirrored on the larger screen — not just selected apps or services. But, wires?

This brings us to Miracast, the middle ground between the two sharing styles. Miracast is a wireless solution that streams the display from a mobile device to a screen — like HDMI without the cables. You also don't need to have a separate wireless network available for the two devices to connect to. Miracast builds on the Wi-Fi Direct protocol to send data from one device to the other, so the connection is made directly — between a phone and a TV, or from a laptop to a monitor. There's no need for passwords, either, so in the examples of Miracast we've seen, it has been a one-button command to create a connection.

Watch Miracast explained by mute cheese sticks in this video from the Wi-Fi Alliance.

You will, of course, need Miracast-compatible devices, and these are pretty rare at this time. But, like we said at the beginning of this article, you will be reading a lot more about Miracast over the next few months.

We recently saw a demo of Miracast using the upcoming LG Optimus G, connecting to a Miracast dongle that plugged in to the HDMI port of a flat-panel TV. The Google Nexus 4 will also be Miracast ready when it launches soon, and the LG reps we spoke with said that Miracast tech will be built in to TVs from next year, removing the need for a dongle. This isn't just for LG devices, though; Miracast is a new industry standard certified by the Wi-Fi Alliance, so all companies will be able to build it into new devices.

The connection we saw demoed took a matter of seconds to establish, and was impressively responsive. There was a tiny bit of latency of maybe half a second between input on the phone's screen and the same response showing on the TV, which could affect the streaming of fast-paced games, but for everything else it is a perfect solution. The icing on the cake was when the LG team started playing a 1080p resolution video stored on the phone's memory, then returned to the home screen and started browsing the web on the phone's display while the movie continued to stream to the TV.

The dongle we saw connected to the TV in our demo was LG branded, and although no final pricing has been confirmed, the LG reps were estimating about AU$70 for the unit. For a device that could replace the need for other smart TV devices, this is an attractive price tag.