Apple TV discovery over Bluetooth

By -cam- posted Apr 21, 2014 04:04 PM


So now that we are all over the excitement of the release of iOS 7.1, lets take a moment to review one of the other interesting features that was released in the Apple ecosystem during this time.


As part of the iOS 7.1 release, Apple also updated the software running on their Apple TV’s and unceremoniously mentioned a new feature in the release notes for the 6.1 Apple TV software (


“Adds support to allow an AirPlay device to discover Apple TV over Bluetooth in environments where multicast or Bonjour traffic is blocked on the network or the AirPlay device is on a different subnet.”


Now that’s sounds interesting but what problem is this trying to solve? My iDevices can happily mirror to my Apple TV at home already without any problems.


Lets take a step back and define the problem here.


When you take a consumer technology like an Apple TV and transplant it into an Enterprise networking environment, things that ‘just worked’ at home aren’t always going to survive the trip.


Corporate networks whether they be in a headquarters office or spread across an education campus are far more complex and less forgiving of the consumer protocols that drive the ‘just work’ mode of home networking.


VLAN’s, routers, broadcast filtering and network design in general are all going to get in the way of many of these enabling technologies such a Bonjour (or mDNS), DLNA and UPnP. All of these acronyms represent individual vendors or industry consortium’s service discovery protocols that were introduced to make their products easier to use and increase adoption by consumers.


So what happens when that first Apple TV gets brought into the office and plugged into the boardroom TV? People just expect it to work like it does at home but the reality is that network design will often prevent this service discovery working as expected.


The Apple TV is plugged into one network and your iPad is on the WiFi network, which in many cases is a different network and therefore no Apple TV’s are found when you go to mirror your screen in the middle of a meeting.


The Industry solution so far . . .


Ok, so now we understand the back-story of the problem, what has everyone being doing to solve this problem to date?


Well many of the networking vendors out there, Aruba included, used their position in the mix between the Apple TV’s and WiFi connected devices to try and solve this problem for their customers.


If an iPad that is trying to find an Apple TV sends out multicast DNS  (mDNS) request and this is dropped at the first VLAN / router boundary, what if the networking vendors could stitch together all these VLAN’s and forward the requests. This means that the iPad on one network will now be able to see the Apple TV on another network.


Problem solved right?


Well No actually. Although this solves one problem, it actually creates a bigger and harder problem to solve and this is where Aruba starts to leave the rest of the networking pack behind.


So you can imagine in a University campus where you have hundreds of lecture theatres and on top of that potentially hundreds of student dorm rooms. What happens if there is an Apple TV is even a small percentage of these lecture theaters and dorm rooms.


If all your networking provider does is stitch together all the VLANs across the campus, you have gone from seeing no Apple TV’s to scrolling through a never ending list of discovered Apple TV’s trying to decipher which one is yours. When it rains it pours I guess.


So Aruba took a slightly different approach when they tried to solve this problem for their customers and introduced a very context aware solution in their AirGroup offering. Instead of blindly forwarding all mDNS requests across the entire network, the AirGroup solution can create a very personalized view of the network and only display for resources that are relevant to you as the end user.


Aruba’s AirGroup technology can take advantage of any (or a combination) of the following pieces of context before deciding to announce the availability of a Bonjour enabled device.


  • Role of the user authenticated to the network (teacher vs student)
  • Service type that is being requested (AirPlay vs AirPrint vs Chromecast)
  • Has the device been registered personally by the user (My AppleTV)
  • Has the user shared his /her device with anyone else (share My Apple TV with room mate in the dorm)
  • Location of the device (printer in reception for printing boarding passes)
  • Assigned group of the device (Apple TV assigned a tag of ClassRoom 7B)
  • Time schedule of use of the device (Economics runs from 10:00-10:45am)


How does Aruba add all of this rich context and flexibility in defining how these devices are seen, shared and utilized on complex enterprise and education networks? It is a technology integration between the Aruba WiFi infrastructure and the ClearPass Access Management platform that provides simple portal through which non-technical users and register and share the devices they bring onto the network. Additionally administrators can register shared devices and define rules on how, where and when the devices should be available.


How does this announcement affect my plans for AirPlay?


So getting back to Apple’s announcement of Bonjour discovery over Bluetooth, what does this actually mean.


Well they have solved one of the key problems addressed by Aruba’s AirGroup technology. That is, if an Apple TV is not on the same network as the requesting iDevice then prior to iOS7 they would not be able to discover each other without some help from the networking vendors. This new capability will allow the Apple TV to fall-back to announcing its presence via Bluetooth to any iOS 7.1 devices close proximity. Assuming there is actually a valid routed network path between the iOS device and the Apple TV, the AirPlay browser will show the Apple TV in question.


That’s great and this might be of great benefit to many customers out there that are just starting their rollout of these AirPlay services. But for many of us that have been working with Bonjour and more recently other service discovery protocols like DLNA (used by Chromecast for example) and UPnP, Aruba’s AirGroup technology still brings an unquestionable amount of value to these deployments.


Bonjour discovery of Apple TV’s via Bluetooth does not help with the other classes of devices such as AirPrint capable printers and the new wave of consumer devices coming from other vendors like Google’s Chromecast, Samsung and many game console providers. These devices are all supported by AirGroup along with the rich context based sharing policies we discussed previously.


What do I need to take advantage of Bonjour discovery over Bluetooth?


There are only three requirements to take advantage of this new discovery method for Apple TV’s.


  • Your iOS devices need to be running iOS 7.1 and make sure they have bluetooth enabled.
  • The Apple TV’s need to updated to the 6.1 software release
  • Finally there needs to be a network route between the wireless network of the iOS device and the network where the Apple TV is connected.


Both iOS 7.1 and Apple TV software release 6.1 were made available on 10th March 2014.


The Bluetooth hardware required to support this technology is based on the Bluetooth 4.0 specification and is available on the following devices from Apple:


  • iPhone 4s or later,
  • iPad (3rd generation or later),
  • iPad mini (1st or 2nd generation),
  • iPod touch (5th generation),
  • Apple TV (3rd generation).


One key thing to be aware of with this solution is that Bluetooth is only being used for discovery of the Apple TV and all of the AirPlay mirroring traffic actually still flows over your wireless network.

Can AirGroup and Bonjour discovery over Bluetooth co-exist?


Absolutely they can co-exist and an AirGroup enabled network will provide an even more personalized experienced for your end users. Although both technologies are seeking to solve the same service discovery over layer 3 network boundary issues, when AirGroup is enabled on your network with an upcoming version of the ArubaOS software, the AirGroup policies and sharing rules will take precedence over the discovery offered by the Apple TV over Bluetooth.


We are certainly excited about this addition of Bluetooth discovery for Apple TV’s and know that it will help in many customer environments but equally motivated to continue innovating on our AirGroup technology to provide even more value for networks that are deploying these consumer technologies.