There are lots of ways for you to enjoy your favorite movies and music. There's streaming services, of course, like Netflix and Spotify. But what about all the flicks and tunes you've downloaded from the Internet or ripped from CDs and DVDs? How can you play your local media on your home TVs and home theater systems?
The key is to set up one of the computers on your home network as a streaming media server. This server than then stream your local media[md]movies, music, and photos[md]to compatible playback devices throughout your home.
How DLNA Works[md]and Sometimes Doesn't
When you want to playback media stored elsewhere in your home, look for a device that is DLNA certified. Said device might be a “smart” TV, networked audio/video receiver, or standalone streaming media player, such as a Roku box or Google Chromecast; just look for the DLNA certification in the specs.
DLNA stands for the Digital Living Network Alliance, a trade organization concerned with the sharing of digital media between multimedia devices. DLNA certification means that the given device can find and play compatible media stored elsewhere on your home network. It's all about interoperability for digital media devices.
A DLNA-certified device uses Universal Plug and Play (UPnP) technology to recognize and control the playback of your digital media. In theory, you should be able to use your DNLA-certified device to navigate to any shared folder on any computer on your network, and open the files found there. That's in theory, anyway.
Sometimes it all works as promised, with the playback device accessing and playing your local media with no problems at all. In other instances, however, UPnP doesn't work completely as promised. Some DLNA-certified devices are limited in the types of files with which they're compatible. Other DLNA-certified devices can't access the host computer, don't see any media files where they're supposed to be, or will have trouble playing back the stored files. It's not a technology standard without its kinks.
For example, you might find that a given DLNA device, like a smart TV, can't see the media files on a given computer on your network. Or perhaps it sees the files but won't play them, or won't play all of them. Or maybe the playback is slow and stuttered.
In my own case, I have a lot of media files in formats that most DLNA-certified devices can't read. While the DLNA standard technically supports just about all major media file formats, individual DLNA devices don't have to (and often don't) be compatible with them all. I happen to have my audio files stored in WMA Lossless format; both my Onkyo A/V receiver and WDTV Live media player will play regular WMA files, but not lossless files. So I can't access my large digital music library from either of these two DLNA devices.
The solution is to make an end run around DLNA and use a streaming media server, instead. Media server software makes media streaming more foolproof; it makes all your files accessible to all the media devices on your network, and even transcodes stored files into formats that can be read by specific media player devices. When DLNA isn't working for you, setting up a streaming media server on your network will more often than not make things right.