The ultimate guide to media streaming
25th Mar 2010 | 10:35
Windows 7 sharing, UPnP, DNLA and more explained
Making streaming simpler
The MP3 codec is 15 years old this year. Unlike its peers, it won't be studying for its GCSEs or sneaking off behind the bike sheds for a quick snog: it'll just be quietly celebrating yet another anniversary as the definitive format for music of our time.
Other technically superior formats have tried to displace it over the last decade and a half, but MP3 is as synonymous with digital music as a certain brand of vacuum cleaner is with cleaning the carpets.
The question this raises is simple: if MP3 and its later video equivalents have been around for all that time, why is it still so hard to stream digital media files from one PC or device to another?
There are loads of clever devices and protocols designed for streaming a song or film off one hard drive, over an IP network and onto a different PC or player – but one manufacturer of both media servers and 2.1 speaker systems told us that it's still far more common for customers to simply unplug a laptop and carry it to another room if it's storing a tune they particularly want to hear. That's just anecdotal evidence, but it wouldn't be at all surprising if true.
There are lots of ways to share media files, but nearly all have pitfalls or compatibility issues that can make physically carrying around the storage seem like the most trouble-free option.
The simplest and most reliable way is to put your media library into one folder on a hard drive, right-click on it and select 'Sharing Options'. You'll need Samba installed if you're using Linux, but other than that it's the work of seconds to open up access to all areas for anyone on your network, so that they can see the contents.
With that access granted, any media player software will let you browse to the appropriate shared folder and play back the media from there.
There are three drawbacks to this approach. The most obvious is that the host PC has to be switched on if you want to watch or listen to something on its hard drive. Many of us will baulk at the idea of leaving two machines running in order to listen to one song.
Even if you don't mind leaving a clown-shoe-sized carbon footprint, or you've built yourself a low-power media centre PC that you're happy to leave running 24/7, there are a couple of other problems that might crop up.
Firstly, getting one PC to see another on a home network isn't always easy. Many novice users accidentally set up two workgroups depending on whether their various PCs have defaulted to 'Home' or 'Workgroup' in the set-up process.
This was one of the problems that Microsoft tried to address with the new Homegroup network setup in Windows 7. And it works perfectly – if every PC is running Windows 7. If you've got a mix of operating systems, it can complicate things a step further for the uninitiated.
Having both 'Homegroups' and 'Network' locations in Windows Explorer is confusing, for a start. More critically, it hides the traditional tree structure of workgroup and member computers, making troubleshooting a missing link that bit harder. (The solution is still to right-click 'Computer' and select 'Properties' followed by 'Change Settings | Change', before adding your Windows 7 machine to the existing workgroup.)
As long as two computers can see each other, it's a simple case of navigating to the folder in Windows Explorer or setting up your local media player to monitor it for contents. Windows Media Player, WinAmp, Rhythmbox et al can keep up to date with a remote library in that way, and it remains the most straightforward means of playing a file stored on one PC on another.
What happens, though, if the device you want to play your media back on doesn't have a file browser? Or if you're running iTunes on one machine, which won't monitor a remote library without duplicating every track locally?
In this age of network-aware TVs and iPods, you need something a bit smarter. Setting up a media server to centralise your music library so that it can be accessed by any device anywhere on your home LAN or beyond isn't, in theory, much harder than folder sharing. You just need a server app that has access to the physical location of your media and compatible client devices that can stream from it.
As far as PC software goes, most common media players – with the exception of Songbird – can act as both client and server, making their libraries accessible to other players and streaming files back from them. Another advantage of using a server rather than a folder share is that several machines will be able to access the same file at once.
The key standards: UPnP and DLNA
There are two standards that new devices or apps come branded with that should ensure any client player carrying the logo can read files from any similarly certified server.
The first is Universal Plug and Play (UPnP), the long-established networking standard designed to do away with micromanaging devices on your network. You'll need a UPnP‑compatible router – but you'll struggle to find one that isn't.
Turning on UPnP in your router's control panel introduces a marginal amount of latency, but it does mean that devices are self-configuring and compatible, so the trade-off is generally worth it. Part of the UPnP standard, UPnP AV, specifically addresses the question of sharing media libraries.
Theoretically, any UPnP playback software or device should be able to read from the library of a UPnP server on the same network. Theoretically.
Depending on how libraries are structured, it can be a bit hit-or-miss as to whether UPnP devices will play together. It's not unusual for a server's library to show up within player software on another PC but appear to be empty of content. (Note, too, that not all UPnP servers and clients handle video and photos as well as music.)
Just because a network-attached storage (NAS) box claims to have a UPnP media server built-in doesn't mean its contents will automatically spring up on the screen of your UPnP TV. It's worth reading reviews that specifically mention streaming abilities before buying a networked hard drive too, as they're not always reliable.
On the upside, though, the fact that DRM-protected files are becoming extinct means that the issues surrounding streaming purchased songs are passing away too. If you've got a large library of restricted audio files and haven't tried streaming them for a while, then it's worth giving it a go again.
After UPnP, the second standard to look for is provided by the Digital Living Network Alliance (DLNA), a working group of most consumer electronics manufacturers who ostensibly want to put the bad old days of proprietary methods of media streaming behind them. The DLNA specifications are built on the foundations of UPnP, but add extra functions specifically to make sharing libraries easier.
DLNA certification is generally more reliable than vanilla UPnP, but it's not foolproof. If a shared library is set up on one device then it should appear automatically in the playback interface on another, such as the PlayStation 3.
Both UPnP and DLNA allow the server to 'push' files to clients too, playing back videos or music from your hard drive to a remote device. Unlike the PS3, the Xbox 360 isn't DLNA-compliant and streaming video to it from anything other than a Windows PC or server to an Xbox can be tricky.
If you don't want to rely on Windows Media Player, there are some good UPnP/DLNA server applications that do recognise Microsoft's games console, such as the commercial TwonkyMedia, the open-source XBMC, TVersity or Majestic.
Just don't try using iTunes unless everything in your house is Apple-branded. Its current method of media streaming – Digital Audio Access Protocol (DAAP) – is proprietary and doesn't handle video.
Not only will TwonkyMedia and so on give you access to your media files from anywhere on your LAN, they'll also transcode video files on the fly, resizing them for handheld devices and smoothing playback over a network.
If you're planning on using a dedicated PC for storing and sharing music and movies, use an OS designed for the purpose. Mythbuntu or the Live version of XMBC are simple Linux distributions, or you could invest in the all-powerful Windows Home Server. The latter will search for and archive all music and movies from any connected machine, and automatically back up other key folders as instructed.
The problem is that it's overkill. All of those tasks can be done for a lot less than the cost of a new PC by a good NAS device such as the Buffalo LinkStation or Netgear Stora. They're not as flexible as a full tower system when it comes to adding more storage, because there's limited space in the cabinet, but they're just as adept at one-touch backups and actively pulling files from any networked PC.
The latest models also give you access to your files from outside your home network, just like Home Server – although with the typical upload speeds of UK broadband still just 1Mbps or lower, don't expect to stream videos to your hotel room at any sort of quality.
USB-to-Ethernet hubs and the cloud
Why go as far as a dedicated NAS device? There's a range of USB-to-Ethernet hubs now available that allow you to connect external hard drives to your network. Dedicated, multiport devices such as the Belkin Home Base may be a bit pricey, but more and more routers – such as Netgear's RangeMax WNDR3700 – are turning up with a single USB port that does the same thing, built-in alongside the Ethernet connections.
One of the advantages of a USB bridge is that it can also hook up printers and scanners so they can be accessed from anywhere. If you want to use one for hard drives, make sure they have a NAS mode, otherwise only one machine will be able to access the drive at a time.
There are two reasons you might want to go for a 'proper' NAS device. The first is that they offer an extra layer of security through RAID mirroring, so you'll have a secondary backup of all your music, video and photo files should disaster strike. The second is that they tend to be a lot faster than networked USB hubs.
Neither will come close to filling a gigabit router's bandwidth, but read and write speeds are often five or six times quicker for NAS units. It's the difference between jitter-free HD video playback and taking all night just to back up a single film.
When it comes to bonus features, the Home Base isn't far behind, competing with high-end NAS devices through its ability to automatically sync photo folders with Flickr or Picasa.
For all the methods of moving your media around a home LAN, the most important factor to consider is the quality of the network itself. As a rule, streaming music from one PC to another is straightforward on any reasonable connection, from older 802.11g wireless kit upwards. Even lossless audio barely takes up a fraction of the available bandwidth of Wireless N, Ethernet or powerline adaptors.
Video, on the other hand, is going to need something faster and more reliable, especially if you plan to watch a lot of HD content remotely. If you don't mind getting out the drill, cabling the house for hard-wired Ethernet is still the most reliable way of shifting content around.
Both 802.11n and Ethernet-over-powerline adaptors designed to the HomePlug AV standard are also capable of handling HD video. Indeed, if you make sure that Quality of Service settings – which prioritise time-sensitive information such as video and voice – are enabled, they might even be better in some cases.
In ideal conditions, the former can provide 300Mbps, while the latter works at 200Mbps, but which one is suitable for you will depend on the construction of your home. In a typical house, you can expect around 140Mbps from both, more than enough for the 20Mbps normally required by HD video.
HomePlug AV turns your mains ring into a giant Ethernet cable, with adaptors that plug into regular power sockets, so it isn't subject to the same dead areas as Wireless-N when it comes to thick walls. If your electrics aren't up to scratch, though, the signal soon degrades as the wiring gets older.
In the cloud
You might want to bypass the home network altogether and leap straight into the cloud by uploading all your media files and taking it from there. Indeed, commercial streaming services including Spotify and Hulu are turning into viable alternatives to owning files, especially if you live in the US, where video-on-demand is well established.
However, what if you want an online repository for files you've already paid for, or can't bear losing the joy of ownership? Well, Logitech's Squeezebox players can connect to a personal MP3 tunes locker into which you upload your tunes.
It's not a terrible idea, but uploading all your MP3s could take a while and only certain bitrates are supported. The same issue affects NAS devices or server software that allows you to stream songs from a home machine to any IP address (see the Linksys Media Hub review).
As far as video goes, you could try setting up a UPnP server on an Amazon cloud server, but we wouldn't recommend it. Of all these different ways to get media off one device and onto another, then, which would we recommend?
The answer: all of them. Rather than looking for a silver bullet to solve all your streaming issues, it's going to be far easier to use a mix of approaches depending on what hardware you already have.
The key thing is to avoid is unnecessary duplication, and planning around your existing network is the most stress-free way of approaching it. And if it turns out that after 15 years the best way of getting an MP3 file from one PC to another is to keep it stored on a USB key, well, that's not so bad, is it?
First published in PC Plus Issue 292
Liked this? Then check out 15 Media Center tweaks and tips for Windows 7
Sign up for TechRadar's free Weird Week in Tech newsletter
Get the oddest tech stories of the week, plus the most popular news and reviews delivered straight to your inbox. Sign up at http://www.techradar.com/register