theChrisWalker.net

You may notice an Xbox360 related theme in my current posts, as after getting one, most of my technology thought process is involved in something to do with it. Hence the Xbox Live Gamercard API I wrote about before. Now we get on to UPnP.

Universal Plug and Play is used for 2 mains things as far as I can tell.

1. Dynamically opening holes in firewalls/NAT configurations for inbound connections to services. (bad!
2. Media Discover/playback/control on a local network. (good!)

The first is bad in my opinion. I don’t want the ability for some software behind my firewall to allow connections into my network. It might make some software function a little more smoothly, but if it’s that important that connections can be made inbound I would have set up a port-forward myself.

So I am only concerned with the second scenario.

The situation was that the Xbox360 can Stream Music/Pictures and Video from a Windows based PC. Great, except if you haven’t got a windows based PC, or you have all your media on a fileserver running Ubuntu Server and don’t want to have to have another PC on just to stream to your Xbox360. So I did some digging and it turns out that the Xbox360 uses a “standardised” UPnP discovery protocol. I say “standardised” because it’s not quite compliant, but close enough.

I look at the options available and try uShare first. It looks good, but the Xbox won’t see it and it can’t read the ID3 info from my music - rendering the whole thing useless.

Next TwonkyMediaServer. I read somewhere that the linux demo doesn’t expire. I hope not, because it worked beautifully pretty much out of the box. The only gripe is that there’s no nice init scripts and I have to run a shell script every time I want to start/stop/status/restart it. But it read my media and the Xbox360 recognised it and I haven’t looked back.

So I thought, Wow, this UPnP thing is pretty cool. but it must be more than this?. So I booted up a Windows7 PC. I had had trouble with this machine because Windows Media Player didn’t like the fact that all my music was on a Read-Only SMB share. That and I hate the way the Windows won’t let you connect to different shares on the host with different credentials! How rubbish!

Still WMP12 didn’t like my read-only filesystem. However, with Twonky running on the network, all the music just “appeared” like magic in the “Other Libraries” section. nice.

Then I thought of another thing that had been annoying me. Why can’t I stream media from my fileserver to my Android phone over Wifi?

Well, guess what? There’s an App for that!

Andromote can connect to UPnP media servers and play back the content. Also, and this is quite cool, I can specifiy the media server as Twonky, specify the Media Renderer (i.e. what plays it) as my Windows7 PC, and use the Andromote App as the Control Point - allow full media browsing, playback, skipping, seeking and volume control of the PC from my phone. Pretty neat, eh?

The whole time, all the servers and renderers are auto-discovered, no configuration necessary. That’s pretty cool.

So in summary UPnP media is in 3 distinct parts and the best bit is that each part can be on a separate physical machine, or 2 on 1, or 1 each on 3 separate physical devices. Very flexible. The parts:

Media Server — Serves the media - duh. i.e. media is physically stored (or accessed from) here.

Media Renderer — Plays back the media - simples.

Media Control Point — Controls the Media. Reads media info and tells the renderer what to play.

So the most common configuration is the server on one machine and the renderer and control point in another. That’s how the Xbox360 works.

So that was my experience into UPNP. I realise now that it was slightly unecessary as my old Xbox, running XBMC, would have (according to their wiki) worked as the UPNP media server out of the box and is conencted to all my shares, and isn’t a hassle to turn on as it sits right next to my Xbox360. It’ll be my fallback if Twonky does expire…