On the Lambda

Programming, Technology, and Systems Administration

On the Lambda

AppleTV vs AirServer in the Classroom

September 24th, 2012 · 3 Comments · networking

AirPlay is fast becoming the go-to protocol for wireless display purposes. There is software to support mirroring your display to a device such as an AppleTV from iOS, OS X, PC, and even Android. In addition to the AppleTV, there are a number of other options to host a mirrored screen. This includes any device capable of running the excellent XMBC software, so dedicated hardware is as cheap as a $35 Raspberri Pi.

Recently I began to support a project that put a new iPad in the hands of about 35 college professors: nearly the entire faculty of the small college where I work. For early trials of the program, we put out a dozen real AppleTV devices and connected them to our classroom projectors, to support using the iPads in class. We are now removing these AppleTVs entirely, in favor of a product called AirServer.

We had a number of reasons for making the switch:

  • I had occasional reports of an AppleTV locking up after about 20 to 30 minutes of continuous use. The PC hardware running AirServer is easily capable running that long.
  • No reset or update issues. In order to prevent theft, we had to hide away the AppleTV units up in the plenum space in the ceiling, making resets difficult on faculty and IT both. This was especially trying when Apple released three software updates in four months. Updates require a click-through with the remote before allowing you to mirror a display, which effectively locked faculty out of the device.
  • No input selection issues. It’s hard to over-state this. We had a number of support issues when one faculty would set a projector or audio input to work with their iPad, and then forget to set it back. The next instructor in the room was not always tech savvy enough even to set it back. By using PC-based software, the workflow is consistent for everyone: log into the PC no matter what, and all audio and video run through there. This is a huge win for those faculty not yet using iPads, and also provided some benefits even to those who were, in the form of having the PC ready and warmed up in case they want to do anything else.
  • Easier to select the right room. With AppleTVs, every classroom was always listed in iOS as available for mirroring. With AirServer, the classroom does not appear until you activate it, making it much less likely to pick the wrong room. Yes, this does happen.
  • Easier Audio setup and support. AppleTV only supports hdmi or fiber audio, and neither was a good fit for our AV setup. This was a weakness of AirServer early on, but now that it’s fully supported AirServer wins here easily.
  • Cost. AirServer worked out to about $3 per classroom for us in purchase costs. That’s not a typo. When you add in cabling and audio converter boxes, AppleTV units were well over $150 each. AppleTVs were more work to set up and maintain as well.
  • Video support. Early on in testing, we were unable to play a simple YouTube over AirServer. For comparison, we tried over an AppleTV as well. We found at the time that the experience on both devices was horrible, but that the AppleTV was still better. This is no longer true. The experience is still less than ideal, but AirServer is now more reliable for this test than a real AppleTV device. In the end, if all you’re doing is showing a YouTube video, why not just use the PC? It’s only when you’re doing this as part of larger demonstration or app that it will matter.
  • Network setup. Because of the old wiring in our old buildings, the AppleTV units were relegated to wifi-only. This limited display quality. AirServer is able to take advantage of the wiring already in use by our classroom PCs, resulting in much-improved quality.
  • Support for multiple simultaneous devices. I haven’t seen anyone actually use this, but on paper AirServer supports up to four devices mirrored to the same screen. AppleTV does not.

I do have a few suggestions for anyone else working with AirServer. The first is to install Bonjour Print Services for Windows before installing AirServer. This was a key step in getting audio and YouTube working for us. It’s possible this is no longer necessary, now that AirServer is no longer in beta, but it certainly doesn’t hurt.

We also had to edit the Windows registry to get the bonjour name and activation to apply to all user profiles on a PC, by loading the hive for the default user. Reportedly this is fixed in the latest update, but it’s no longer a problem for us so I haven’t needed to find out.

We had to re-think our classroom network setup so that classroom computers appeared on the same network segment as wireless devices in the area, and re-work our wireless network setup so that we know for sure which network segment that will be. This was a big project that’s still not entirely closed.

Finally, we did not elect to have AirServer start automatically. The option seemed to cause reliability issues and make error messages show up at log in.

Overall, AirServer was a huge improvement over an AppleTV for classroom use. When we began the switch-over to AirServer from AppleTV, AirServer for Windows was still in beta, but now that it’s released I can recommend it whole-heartedly.


3 Comments so far ↓

  • Bryan Bentley

    Thank you for sharing this information. You speak of a registry fix in Windows 7 for the license to transfer to all user profiles. Can you please share that registry fix? I’ve downloaded the latest version of AirServer and noticed that it prompts for a license key when a new user logs in.

  • Dave B

    Ya, thanks for the information! I’m working to implement this myself at our campus. I ran into the same issue with the activation needing to be applied to all user accounts. What registry tweak did you do to make that happen?

    • jcoehoorn

      From what I read, multi-user activation shouldn’t be a problem anymore with the last few versions of AirServer. But, if it’s not working for you, I can share what we did. It’s not simple.

      What we had to do was activate it on a specific account. Then we opened up regedit, found the AirServer key in HKCU\Software\AirServer, and copied the registration key created there to the clipboard. Next, you have to load the Default User’s hive into regedit (look under File->Load Hive). The profile is typically located at C:\Users\Default\NTUser.dat, and you have to set the folder to show protected operating system files to be able to find it. With this hive loaded, you can now paste the registration key to the same location relative to this profile. Unload the hive, and there you go: AirServer will be activated for any new profile on that system.

      We used the same technique to set the appropriate machine name. It worked because we did this at the same time that we re-installed other things, so there were no prior profiles to worry about. If you need to preserve existing profiles, or use roaming profiles, you need to set this key on every existing profile.

      Again: I’ve heard this is fixed now, which means they likely store this in HKLM where it belongs.

Leave a Reply to Dave B