Why your iOS device with the AT&T SIM automatically join to an AT&T Wi-Fi Hotspot aka "attwifi - Passpoint" without any user settings.
AT&TのSIMを挿したiPhoneは、何故自動的にAT&TのPasspoint基地局にWi-Fi接続するのか
Let me jump to the conclusion.
The Carrier Bundles from AT&T includes a profile to connect AT&T Wi-Fi Hotspot (Passpoint).
I read some AT&T user's point in the forum like below;
How to Disable ATT Passpoint IPhone 8+ iOS 11.0.2
Yesterday I was at a HomeDepot and nothing was loading on my phone. It turned out I was on ATT-Passpoint WiFi. Not LTE. The phone won’t let me “forget” that ssid and when I toggle AutoJoin off it just switches back on.
I don’t care what security ATT passpoint uses I just don’t want to auto join any public WiFi system. Anyone know how to disable this?
https://forums.att.com/t5/Apple/How-to-Disable-ATT-Passpoint-IPhone-8-iOS-11-0-2/td-p/5287613
Forced to join attwifi since iOS 11!!!!!
According to AT&T's info here https://passpoint.attwifi.com/ an iPhone needs a Passpoint profile installed to automatically connect. However, my phone does not have any profile installed. I imagine that they updated the carrier settings to "force" configure the phone to work with Passpoint if WiFi Calling is enabled, perhaps to coincide with the iOS11 release.
https://forums.imore.com/ask-question/394777-forced-join-attwifi-since-ios-11-a.html
And yes, Here is the mecanism.
AT&T updated with thier "Carrie Bundles" with iOS11.
We can see what does it have.
The following link is the apple carrier bundle list:
https://itunes.apple.com/WebObjects/MZStore.woa/wa/com.apple.jingle.appserver.client.MZITunesClientCheck/version
It has the BundleURL list, iOS11.1 will see this URL.
<key>ATT_US</key> <dict> --- snip -- <key>11.1</key> <dict> <key>BuildVersion</key> <string>30.1</string> <key>BundleURL</key> <string>http://appldnld.apple.com/ios11.1/carrierbundles/091-43117-20171030-22774A0C-BD87-11E7-92F2-91FF17FB103A/ATT_US_iPhone.ipcc</string> <key>Digest</key> <data> +0Eoo93OM5FX2iXr6WiHNRQDHr0= </data> </dict> --- snip --- </dict>
The .ipcc file is ZIP archive.
Here is file list.
Dutch.lproj hi.lproj overrides_N56_N61.pri English.lproj hr.lproj overrides_N66_N71.der.pri French.lproj hu.lproj overrides_N66_N71.plist German.lproj id.lproj overrides_N69.plist Info.plist ko.lproj overrides_N69.pri Italian.lproj ms.lproj pl.lproj Japanese.lproj no.lproj profile.mobileconfig Spanish.lproj overrides_D101_D111.der.pri pt.lproj ar.lproj overrides_D101_D111.plist pt_PT.lproj ca.lproj overrides_D10_D11.der.pri ro.lproj carrier.plist overrides_D10_D11.plist ru.lproj cs.lproj overrides_D201_D211.der.pri signatures da.lproj overrides_D201_D211.plist sk.lproj el.lproj overrides_D20_D21.der.pri sv.lproj en_AU.lproj overrides_D20_D21.plist th.lproj en_GB.lproj overrides_D22.der.pri tr.lproj es_MX.lproj overrides_D22.plist uk.lproj fi.lproj overrides_D221.der.pri version.plist fr_CA.lproj overrides_D221.plist vi.lproj global_setting_A.gri overrides_N51_N53.plist zh_CN.lproj global_setting_B.gri overrides_N51_N53.pri zh_HK.lproj he.lproj overrides_N56_N61.plist zh_TW.lproj
The profile.mobileconfig include the settings to autojoin the network of AT&T Wi-Fi Passpoint with the EAP-SIM/AKA authentication.
It does not have SSID as attwifi-Passpoint because it is Passpoint.
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>PayloadContent</key> <array> <dict> <key>PayloadDescription</key> <string>Configures device restrictions.</string> <key>PayloadDisplayName</key> <string>Restrictions</string> <key>PayloadIdentifier</key> <string>com.apple.attwifi.restrictions</string> <key>PayloadOrganization</key> <string>Apple Inc</string> <key>PayloadType</key> <string>com.apple.applicationaccess</string> <key>PayloadUUID</key> <string>E1390FCE-911C-4B64-B352-8CE4B5E3A891</string> <key>PayloadVersion</key> <integer>1</integer> <key>allowAddingGameCenterFriends</key> <true/> <key>allowAppInstallation</key> <true/> <key>allowCamera</key> <true/> <key>allowExplicitContent</key> <true/> <key>allowGlobalBackgroundFetchWhenRoaming</key> <true/> <key>allowInAppPurchases</key> <true/> <key>allowMultiplayerGaming</key> <true/> <key>allowSafari</key> <true/> <key>allowScreenShot</key> <true/> <key>allowVideoConferencing</key> <true/> <key>allowVoiceDialing</key> <true/> <key>allowYouTube</key> <true/> <key>allowiTunes</key> <true/> <key>forceEncryptedBackup</key> <false/> <key>ratingApps</key> <integer>1000</integer> <key>ratingMovies</key> <integer>1000</integer> <key>ratingRegion</key> <string>us</string> <key>ratingTVShows</key> <integer>1000</integer> <key>safariAcceptCookies</key> <integer>2</integer> <key>safariAllowAutoFill</key> <true/> <key>safariAllowJavaScript</key> <true/> <key>safariAllowPopups</key> <true/> <key>safariForceFraudWarning</key> <false/> </dict> <dict> <key>EncryptionType</key> <string>None</string> <key>HIDDEN_NETWORK</key> <false/> <key>IsHotspot</key> <true/> <key>PayloadDescription</key> <string>Configures wireless connectivity settings.</string> <key>PayloadDisplayName</key> <string>Wi-Fi (attwifi)</string> <key>PayloadIdentifier</key> <string>com.apple.attwifi.wifi</string> <key>PayloadOrganization</key> <string>Apple Inc</string> <key>PayloadType</key> <string>com.apple.wifi.managed</string> <key>PayloadUUID</key> <string>9CB34BD4-FF73-4E49-8474-DA475B13E2C6</string> <key>PayloadVersion</key> <integer>1</integer> <key>SSID_STR</key> <string>attwifi</string> </dict> <dict> <key>AutoJoin</key> <true/> <key>DisplayedOperatorName</key> <string>AT&T Wi-Fi Passpoint</string> <key>DomainName</key> <string>attwifi.com</string> <key>EAPClientConfiguration</key> <dict> <key>AcceptEAPTypes</key> <array> <integer>23</integer> </array> <key>EAPSIMAKAConservativePeer</key> <true/> <key>EAPSIMAKAPsudeonymIdentityLifetimeHours</key> <integer>24</integer> </dict> <key>EncryptionType</key> <string>WPA2</string> <key>IsHotspot</key> <true/> <key>MCCAndMNCs</key> <array> <string>310410</string> </array> <key>PayloadDescription</key> <string>Configures Wi-Fi settings</string> <key>PayloadDisplayName</key> <string>WiFi</string> <key>PayloadIdentifier</key> <string>com.apple.attwifi.com.apple.wifi.managed.C7F682EC-9305-4E07-A1AB-BEB24B1E5611</string> <key>PayloadType</key> <string>com.apple.wifi.managed</string> <key>PayloadUUID</key> <string>865A5DF1-1AE7-4659-85D8-B686E29BB1AE</string> <key>PayloadVersion</key> <integer>1</integer> <key>ProxyType</key> <string>None</string> <key>ServiceProviderRoamingEnabled</key> <true/> </dict> </array> <key>PayloadDescription</key> <string>Auto-joins the attwifi Wi-Fi network</string> <key>PayloadDisplayName</key> <string>attwifi</string> <key>PayloadIdentifier</key> <string>com.apple.attwifi</string> <key>PayloadOrganization</key> <string>Apple Inc</string> <key>PayloadRemovalDisallowed</key> <false/> <key>PayloadType</key> <string>Configuration</string> <key>PayloadUUID</key> <string>7156353A-F9C3-42AE-A781-2DD301ACBBD0</string> <key>PayloadVersion</key> <integer>1</integer> </dict> </plist>
