Apple TV,  Mac OS X,  Mac OS X Server,  Mac Security

The AppleTV Software Update Feed

April 27, 2016

AppleTVs automatically update. They do so using a process similar to how iOS updates, but instead of looking at the feed I posted in https://krypted.com//mac-security/how-the-os-x-caching-server-caches-updates/, they look at http://mesu.apple.com/assets/tv/com_apple_MobileAsset_SoftwareUpdate/com_apple_MobileAsset_SoftwareUpdate.xml.

The AppleTV feed is similar to that available for iOS updates, with each dictionary having roughly the same data:

<key>ActualMinimumSystemPartition</key>
<integer>1482</integer>
<key>Build</key>
<string>13Y6234</string>
<key>InstallationSize</key>
<string>0</string>
<key>MinimumSystemPartition</key>
<integer>1534</integer>
<key>OSVersion</key>
<string>9.2</string>
<key>ReleaseType</key>
<string>Beta</string>
<key>SUDocumentationID</key>
<string>PreRelease</string>
<key>SUInstallTonightEnabled</key>
<true/>
<key>SUMultiPassEnabled</key>
<true/>
<key>SUProductSystemName</key>
<string>iOS</string>
<key>SUPublisher</key>
<string>Apple Inc.</string>
<key>SupportedDeviceModels</key>
<array>
<string>J42dAP</string>
</array>
<key>SupportedDevices</key>
<array>
<string>AppleTV5,3</string>
</array>
<key>SystemPartitionPadding</key>
<dict>
<key>1024</key>
<integer>1280</integer>
<key>128</key>
<integer>1280</integer>
<key>16</key>
<integer>160</integer>
<key>256</key>
<integer>1280</integer>
<key>32</key>
<integer>320</integer>
<key>512</key>
<integer>1280</integer>
<key>64</key>
<integer>640</integer>
<key>768</key>
<integer>1280</integer>
<key>8</key>
<integer>80</integer>
</dict>
<key>_CompressionAlgorithm</key>
<string>zip</string>
<key>_DownloadSize</key>
<integer>856434408</integer>
<key>_EventRecordingServiceURL</key>
<string>https://xp.apple.com/report</string>
<key>_IsZipStreamable</key>
<true/>
<key>_Measurement</key>
<data>cm8k41In38EOJEj20IwJp5Suskw=</data>
<key>_MeasurementAlgorithm</key>
<string>SHA-1</string>
<key>_UnarchivedSize</key>
<integer>3438532888</integer>
<key>__AssetDefaultGarbageCollectionBehavior</key>
<string>NeverCollected</string>
<key>__BaseURL</key>
<string>
http://appldnld.apple.com/tvOS9.2//031-53364-20160321-7C5E21F2-E7B5-11E5-89F7-525CBD379832/
</string>
<key>__CanUseLocalCacheServer</key>
<true/>
<key>__RelativePath</key>
<string>
com_apple_MobileAsset_SoftwareUpdate/f58f4b324a9c717ea57b0cee063473a99d9e9e92.zip
</string>
To construct a URL to a zip, you would then simply merge the _BaseURL and the _RelativePath to the asset from the feed for a given model, in the above example, ending up with the following URL to manually download tvOS 9.2 for AppleTV 5,3:
http://appldnld.apple.com/tvOS9.2//031-53364-20160321-7C5E21F2-E7B5-11E5-89F7-525CBD379832/com_apple_MobileAsset_SoftwareUpdate/f58f4b324a9c717ea57b0cee063473a99d9e9e92.zip
BTW, Applednld is load balanced between 17.253.29.201 and 17.253.29.202, both within Apple’s Class C.
You don’t need two / characters in the path, but if you take the same process from my earlier post, you end up with
http://10.1.1.2:55491/tvOS9.2/031-53364-20160321-7C5E21F2-E7B5-11E5-89F7-525CBD379832/f58f4b324a9c717ea57b0cee063473a99d9e9e92.zip?source=appldnld.apple.com