Hello, We are implementing a Transparent Proxy using NETransparentProxyProvider and configuring NETransparentProxyNetworkSettings with NENetworkRule. Currently, NENetworkRule requires: NENetworkRule( destinationHost: NWHostEndpoint(hostname: String, port: String), protocol: .TCP / .UDP / .any ) NWHostEndpoint.port accepts only a single port value (as a String) or an empty string for all ports. At present, we are creating a separate NENetworkRule for each port in the range (ex for range 49152–65535 approximately 16,384 rules). After deploying this configuration, we observe the following behavior: nesessionmanager starts consuming very high CPU (near 100%) The system becomes unresponsive The device eventually hangs and restarts automatically The behavior resembles a kernel panic scenario This strongly suggests that creating thousands of NENetworkRule entries may not be a supported or scalable approach. Questions: Is there any officially supported way to specify a port range in NENetworkRule? Is creating thousands of rules (one per port) considered acceptable or supported? Is the recommended design to intercept broadly (e.g., port = "") and filter port ranges inside handleNewTCPFlow / handleNewUDPFlow instead? Are there documented system limits for the number of NENetworkRule entries allowed in NETransparentProxyNetworkSettings?

I'm using a Mac Studio in a homelab context and use Homebrew to manage the installed services. The services include things that access the local network, for example Prometheus which monitors some other servers, a reverse proxy which fronts other web services on the network, and a DNS server which can use another as upstream. Local Network Access permissions make it impossible to reliably perform unattended updates of services because an updated binary requires a GUI login to grant local network permissions (again). I use brew services to manage the services as launchd agents, i.e. they run in a non-root GUI context. I know that I can also use sudo brew services which instead installs the services as launchd daemons, but running services as root has negative security implication and generally doesn't look like a good idea to me. If only there was a way to disable local network access checks altogether…

There are multiple report of crashes on URLConnectionLoader::loadWithWhatToDo. The crashed thread in the stack traces pointing to calls inside CFNetwork which seems to be internal library in iOS. The crash has happened quite a while already (but we cannot detect when the crash started to occur) and impacted multiple iOS versions recorded from iOS 15.4 to 18.4.1 that was recorded in Xcode crash report organizer so far. Unfortunately, we have no idea on how to reproduce it yet but the crash keeps on increasing and affect more on iOS 18 users (which makes sense because many people updated their iOS to the newer version) and we haven’t found any clue on what actually happened and how to fix it on the crash reports. What we understand is it seems to come from a network request that happened to trigger the crash but we need more information on what (condition) actually cause it and how to solve it. Hereby, I attach sample crash report for both iOS 15 and 18. I also have submitted a report (that include more crash reports) with number: FB17775979. Will appreciate any insight regarding this issue and any resolution that we can do to avoid it. iOS 15.crash iOS 18.crash

NWPathMonitor appears to retain itself (or is retained by some internal infrastructure) once it has been started until cancelled. This seems like it can lead to memory leaks if the references to to the monitor are dropped. Is this behavior documented anywhere? func nwpm_self_retain() { weak var weakRef: NWPathMonitor? autoreleasepool { let monitor: NWPathMonitor = NWPathMonitor() weakRef = monitor monitor.start(queue: .main) // monitor.cancel() // assertion fails unless this is called } assert(weakRef == nil) } nwpm_self_retain()

We’re implementing VPN application using the WireGuard protocol and aiming to support both split-tunnel and per-app VPN configurations. Each mode works correctly on its own: per-app VPN functions well when configured with a full tunnel and split-tunnel works as expected when per-app is disabled. However, combining both configurations leads to issues. Specifically, the routing table is not set up properly, resulting in traffic that should not be routed through the tunnel is routed through the tunnel. Detailed description: Through our backend, we are pushing these two plist files to the iPad one after the other: VPN config with allowed IPs 1.1.1.1/32 <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE plist PUBLIC "-//Apple Inc//DTD PLIST 1.0//EN" http://www.apple.com/DTDs/PropertyList-1.0.dtd> <plist version="1.0"> <dict> <key>PayloadUUID</key> <string>3fd861df-c917-4716-97e5-f5e96452436a</string> <key>PayloadVersion</key> <integer>1</integer> <key>PayloadOrganization</key> <string>someorganization</string> <key>PayloadIdentifier</key> <string>config.11ff5059-369f-4a71-afea-d5fdbfa99c91</string> <key>PayloadType</key> <string>Configuration</string> <key>PayloadDisplayName</key> <string> test</string> <key>PayloadDescription</key> <string>(Version 13) </string> <key>PayloadRemovalDisallowed</key> <true /> <key>PayloadContent</key> <array> <dict> <key>VPN</key> <dict> <key>AuthenticationMethod</key> <string>Password</string> <key>ProviderType</key> <string>packet-tunnel</string> <key>OnDemandUserOverrideDisabled</key> <integer>1</integer> <key>RemoteAddress</key> <string>172.17.28.1:51820</string> <key>OnDemandEnabled</key> <integer>1</integer> <key>OnDemandRules</key> <array> <dict> <key>Action</key> <string>Connect</string> </dict> </array> <key>ProviderBundleIdentifier</key> <string>some.bundle.id.network-extension</string> </dict> <key>VPNSubType</key> <string>some.bundle.id</string> <key>VPNType</key> <string>VPN</string> <key>VPNUUID</key> <string>d2773557-b535-414f-968a-5447d9c02d52</string> <key>OnDemandMatchAppEnabled</key> <true /> <key>VendorConfig</key> <dict> <key>VPNConfig</key> <string> Some custom configuration here </string> </dict> <key>UserDefinedName</key> <string>TestVPNServerrra</string> <key>PayloadType</key> <string>com.apple.vpn.managed.applayer</string> <key>PayloadVersion</key> <integer>1</integer> <key>PayloadIdentifier</key> <string>vpn.5e6b56be-a4bb-41a5-949e-4e8195a83f0f</string> <key>PayloadUUID</key> <string>9bebe6e2-dbef-4849-a1fb-3cca37221116</string> <key>PayloadDisplayName</key> <string>Vpn</string> <key>PayloadDescription</key> <string>Configures VPN settings</string> <key>PayloadOrganization</key> <string>someorganization</string> </dict> </array> </dict> </plist> Command to set up per-app with Chrome browser <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE plist PUBLIC "-//Apple Inc//DTD PLIST 1.0//EN" http://www.apple.com/DTDs/PropertyList-1.0.dtd> <plist version="1.0"> <dict> <key>Command</key> <dict> <key>Settings</key> <array> <dict> <key>Identifier</key> <string>com.google.chrome.ios</string> <key>Attributes</key> <dict> <key>VPNUUID</key> <string>d2773557-b535-414f-968a-5447d9c02d52</string> <key>TapToPayScreenLock</key> <false /> <key>Removable</key> <true /> </dict> <key>Item</key> <string>ApplicationAttributes</string> </dict> </array> <key>RequestType</key> <string>Settings</string> </dict> <key>CommandUUID</key> <string>17ce3e19-35ef-4dbc-83d9-4ca2735ac430</string> </dict> </plist> From the log we see that our VPN application set up allowed IP 1.1.1.1 via NEIPv4Settings.includedRoutes but system routing all of the Chrome browser traffic through our application. Is this expected Apple iOS behavior, or are we misconfiguring the profiles?

I'm developing an application using the accessory setup kit (BLE) on iOS 18+. An important aspect of the connection process is being able to find and choose the correct device. I noticed on iOS 18.2 that I was able to both scroll through the discovered accessories as well as view the advertised name. However, after upgrading to 18.7.2, only a single device is viewable and the advertised name is no longer available. Is there a trigger for this feature that I need to enable or was this "multiple discovery" feature removed? If so, why?

I'm trying to implement support for grpc http/2 streams using NSURLSession. Almost everything works fine, data streaming is flowing from the server and from the client and responses are coming through my NSURLSessionTaskDelegate. I'm getting the responses and streamed data through the appropriate handlers (didReceiveData, didReceiveResponse). However, I cannot seem to find an API to access the trailers expected by grpc. Specifically, the expected trailer "grpc-status: 0" is in the response, but after the data. Is there no way to gain access to trailers in the NSURLSession Framework?

In our system, when a user enables a mobile hotspot and the system connects to it, the system attempts to verify WIFI availability by sending an HTTP GET request to http://captive.apple.com. Normally, the server returns: HTTP Status: 200 (OK) Content-Type: text/html This has always been used as a sign of normal connectivity. Issue: Since last Friday, the server sometimes responds with: Content-Type: application/octet-stream When this occurs, our system determines that the network is unavailable and displays a connection warning (a “!” icon). Question: Has Apple recently made any backend or CDN configuration changes to captive.apple.com that could affect the response type? Any advice how can we solve this problem? Thanks!

The environment: macOS 12.0 ~ 15.6 A NetworkExtension NEFilterDataProvider configured with filterSockets = YES, filterPackets = NO, and it doesn't actually block any network connection. QQMusic (download: https://y.qq.com/n/ryqq/download_detail/mac?ADTAG=YQQ) is constantly playing. Any of the following operations can reproduce the issue: Kill the NetworkExtension process and then restarted by the system. Disable the NEFilterDataProvider, and then enable it. When this problem occurs, there are two different phenomena on the NetworkExtension process: It is zombie, or is in high CPU state (100%). When the NetworkExtension process is zombie, obviously, the new network connections will enter it, and they can't be disposed by the old zombie process, so the network is disconnected. Spindump-qqmusic-ne-zombie When the NetworkExtension process is in high CPU state, its thread DispatchQueue "NEFilterExtensionProviderContext queue" is blocked in the kernel when calling close. Spindump-qqmusic-ne-cpuhigh In most cases, the network will recover after stopping QQ Music, that is the suspended zombie NetworkExtension process will exist or the cpu of it return to normal. To reproduce the issue in a simple environment, I have tried many ways to simulate the network behavior of QQMusic, but all failed. It seems that this issue is caused by UDP traffic of QQMusic, because everything is ok after blocking the UDP connections of QQMusic (the music is still playing at this time) in the NEFilterDataProvider.

I have been playing around with the new URL Filtering API. I have successfully installed and configured the sample code, Installed the example app to my iPhone, and am also running the PIR server locally on my Mac. In my input.txtpb file, I simply have 2 endpoints: rows: [{ keyword: "instagram.com", value: "1" }, { keyword: "youtube.com/shorts", value: "1" }] Neither of these are blocked when I attempt to load them from either a browser, or their dedicated apps. Are there any debugging tips I should know about? Additionally, I have also noticed a few times I have left the filter running on my phone, after leaving my LAN (where the PIR server is running), suddenly throughout the day I'm having random, completely unrelated endpoints blocked on my phone. I thought this API was never supposed to produce false positives (without calling back to the PIR server for confirmation).

I am trying to setup a system-wide DNS-over-TLS for iOS that can be turned off and on from within the app, and I'm struggling with the implementation details. I've searched online, searched forums here, used ChatGPT, and I'm getting conflicting information or code that is simply wrong. I can't find example code that is valid and gets me moving forward. I think I need to use NEDNSProxyProvider via the NetworkExtension. Does that sound correct? I have NetworkExtension -> DNS Proxy Capability set in both the main app and the DNSProxy extension. Also, I want to make sure this is even possible without an MDM. I see conflicting information, some saying this is opened up, but things like https://developer.apple.com/documentation/Technotes/tn3134-network-extension-provider-deployment saying a device needs to be managed. How do private DNS apps do this without MDM? From some responses in the forums it sounds like we need to parse the DNS requests that come in to the handleNewFlow function. Is there good sample code for this parsing? I saw some helpful information from Eskimo (for instance https://developer.apple.com/forums/thread/723831 ) and Matt Eaton ( https://developer.apple.com/forums/thread/665480 )but I'm still confused. So, if I have a DoT URL, is there good sample code somewhere for what startProxy, stopProxy, and handleNewFlow might look like? And valid code to call it from the main app?

I am using Network framework for connecting two iPad devices that are connected through LAN and has Wifi enabled. I have enabled peerToPeerIncluded. I would like to understand how the framework chooses the interface types for browsing and discovering devices. When I start a browser with browser.run or listener.run, does the browser and advertiser browse and listen on all available interface types? My concern is that if it does in only one interface, Is there a chance that the browser is browsing in one interface(Lets say WiredEthernet) and the listener is listening on another interface(Lets say AWDL) and they dont discover?

I'm struggling to understand why the async-await version of URLSession download task APIs do not call the delegate functions, whereas the old non-async version that returns a reference to the download task works just fine. Here is my sample code: class DownloadDelegate: NSObject, URLSessionDownloadDelegate { func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didWriteData bytesWritten: Int64, totalBytesWritten: Int64, totalBytesExpectedToWrite: Int64) { // This only prints the percentage of the download progress. let calculatedProgress = Float(totalBytesWritten) / Float(totalBytesExpectedToWrite) let formatter = NumberFormatter() formatter.numberStyle = .percent print(formatter.string(from: NSNumber(value: calculatedProgress))!) } } // Here's the VC. final class DownloadsViewController: UIViewController { private let url = URL(string: "https://pixabay.com/get/g0b9fa2936ff6a5078ea607398665e8151fc0c10df7db5c093e543314b883755ecd43eda2b7b5178a7e613a35541be6486885fb4a55d0777ba949aedccc807d8c_1280.jpg")! private let delegate = DownloadDelegate() private lazy var session = URLSession(configuration: .default, delegate: delegate, delegateQueue: nil) // for the async-await version private var task: Task&lt;Void, Never&gt;? // for the old version private var downloadTask: URLSessionDownloadTask? override func viewWillAppear(_ animated: Bool) { super.viewWillAppear(animated) task?.cancel() task = nil task = Task { let (_, _) = try! await session.download(for: URLRequest(url: url)) self.task = nil } // If I uncomment this, the progress listener delegate function above is called. // downloadTask?.cancel() // downloadTask = nil // downloadTask = session.downloadTask(with: URLRequest(url: url)) // downloadTask?.resume() } } What am I missing here?

Since updating to macOS 26.4 developerbeta 2 I've been getting full loss of dns resolution. I am not running a VPN or any network extensions that I am aware of. I'm not sure how to report this in the feedback utility as I cannot find an appropriate category for it. Happy to file it if someone can give an appropriate suggestion - the closest I could see was Wi-Fi but that wanted Wi-Fi logs for the issue, which I do not believe to be needed as this is not a Wi-Fi connectivity issue. Running dig example.com +short nslookup example.com ping example.com Gives the following output 104.18.27.120 104.18.26.120 Server: 10.0.1.1 Address: 10.0.1.1#53 \ Non-authoritative answer: Name: example.com Address: 104.18.26.120 Name: example.com Address: 104.18.27.120 \ ping: cannot resolve example.com: Unknown host This shows it's not an issue with my local network and that core networking is working, but something in the mDNSResponder/dns stack of macOS is failing. This causes all apps/browsers that do not implement their own DNS lookups to fail (Chrome still works). Sometimes the issue clears after running the following commands (for a period), sometimes it does not. A restart always resolves the issue temporarily. sudo killall -9 mDNSResponder sudo killall -9 mDNSResponderHelper sudo dscacheutil -flushcache sudo ifconfig en0 down sudo ifconfig en0 up

Hi, On macOS 26.4 Beta (25E5218f) （macOS Tahoe 26 Developer Beta ）, the network filter causes network failures or slowdowns. This manifests as Chrome failing to access websites, while Safari can access the same websites without issue. The affected websites can be pinged locally. My situation is similar to this situation.The same question link is: https://github.com/objective-see/LuLu/issues/836 Have you been paying attention to this issue? Hopefully, it can be fixed in the official release. Thank you.

Dear Apple Developer Support Team, I am writing to inquire about the process for obtaining approval for the following entitlement in my iOS/macOS app: <key>com.apple.developer.networking.networkextension</key> <array> <string>content-filter-provider</string> </array> Specifically, I would like guidance on: The steps required to submit a request for this entitlement. Any necessary documentation or justification that needs to be provided to Apple. Typical review timelines and approval criteria. Any restrictions or compliance requirements associated with this entitlement. Our app intends to implement a content filtering functionality to enhance network security and user safety. We want to ensure full compliance with Apple’s policies and guidelines. Could you please provide detailed instructions or point us to the relevant resources to initiate this approval process? Thank you for your assistance.

I've recently updated one of our CI mac mini's to Sequoia in preparation for the transition to Tahoe later this year. Most things seemed to work just fine, however I see this dialog whenever the UI Tests try to run. This application BoostBrowerUITest-Runner is auto-generated by Xcode to launch your application and then run your UI Tests. We do not have any control over it, which is why this is most surprising. I've checked the codesigning identity with codesign -d -vvvv as well as looked at it's Info.plist and indeed the usage descriptions for everything are present (again, this is autogenerated, so I'm not surprised, but just wanted to confirm the string from the dialog was coming from this app) &lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"&gt; &lt;plist version="1.0"&gt; &lt;dict&gt; &lt;key&gt;BuildMachineOSBuild&lt;/key&gt; &lt;string&gt;22A380021&lt;/string&gt; &lt;key&gt;CFBundleAllowMixedLocalizations&lt;/key&gt; &lt;true/&gt; &lt;key&gt;CFBundleDevelopmentRegion&lt;/key&gt; &lt;string&gt;en&lt;/string&gt; &lt;key&gt;CFBundleExecutable&lt;/key&gt; &lt;string&gt;BoostBrowserUITests-Runner&lt;/string&gt; &lt;key&gt;CFBundleIdentifier&lt;/key&gt; &lt;string&gt;company.thebrowser.Browser2UITests.xctrunner&lt;/string&gt; &lt;key&gt;CFBundleInfoDictionaryVersion&lt;/key&gt; &lt;string&gt;6.0&lt;/string&gt; &lt;key&gt;CFBundleName&lt;/key&gt; &lt;string&gt;BoostBrowserUITests-Runner&lt;/string&gt; &lt;key&gt;CFBundlePackageType&lt;/key&gt; &lt;string&gt;APPL&lt;/string&gt; &lt;key&gt;CFBundleShortVersionString&lt;/key&gt; &lt;string&gt;1.0&lt;/string&gt; &lt;key&gt;CFBundleSignature&lt;/key&gt; &lt;string&gt;????&lt;/string&gt; &lt;key&gt;CFBundleSupportedPlatforms&lt;/key&gt; &lt;array&gt; &lt;string&gt;MacOSX&lt;/string&gt; &lt;/array&gt; &lt;key&gt;CFBundleVersion&lt;/key&gt; &lt;string&gt;1&lt;/string&gt; &lt;key&gt;DTCompiler&lt;/key&gt; &lt;string&gt;com.apple.compilers.llvm.clang.1_0&lt;/string&gt; &lt;key&gt;DTPlatformBuild&lt;/key&gt; &lt;string&gt;24A324&lt;/string&gt; &lt;key&gt;DTPlatformName&lt;/key&gt; &lt;string&gt;macosx&lt;/string&gt; &lt;key&gt;DTPlatformVersion&lt;/key&gt; &lt;string&gt;15.0&lt;/string&gt; &lt;key&gt;DTSDKBuild&lt;/key&gt; &lt;string&gt;24A324&lt;/string&gt; &lt;key&gt;DTSDKName&lt;/key&gt; &lt;string&gt;macosx15.0.internal&lt;/string&gt; &lt;key&gt;DTXcode&lt;/key&gt; &lt;string&gt;1620&lt;/string&gt; &lt;key&gt;DTXcodeBuild&lt;/key&gt; &lt;string&gt;16C5031c&lt;/string&gt; &lt;key&gt;LSBackgroundOnly&lt;/key&gt; &lt;true/&gt; &lt;key&gt;LSMinimumSystemVersion&lt;/key&gt; &lt;string&gt;13.0&lt;/string&gt; &lt;key&gt;NSAppTransportSecurity&lt;/key&gt; &lt;dict&gt; &lt;key&gt;NSAllowsArbitraryLoads&lt;/key&gt; &lt;true/&gt; &lt;/dict&gt; &lt;key&gt;NSAppleEventsUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSBluetoothAlwaysUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSCalendarsUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSCameraUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSContactsUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSDesktopFolderUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSDocumentsFolderUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSDownloadsFolderUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSFileProviderDomainUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSFileProviderPresenceUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSLocalNetworkUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSLocationUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSMicrophoneUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSMotionUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSNetworkVolumesUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSPhotoLibraryUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSRemindersUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSRemovableVolumesUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSSpeechRecognitionUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSSystemAdministrationUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;NSSystemExtensionUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;key&gt;OSBundleUsageDescription&lt;/key&gt; &lt;string&gt;Access is necessary for automated testing.&lt;/string&gt; &lt;/dict&gt; &lt;/plist&gt; Additionally, spctl --assess --type execute BoostBrowserUITests-Runner.app return an exit code of 0 so I assume that means it can launch just fine, and applications are allowed to be run from "anywhere" in System Settings. I've found the XCUIProtectedResource.localNetwork value, but it seems to only be accessible on iOS for some reason (FB17829325). I'm trying to figure out why this is happening on this machine so I can either fix our code or fix the machine. I have an Apple script that will allow it, but it's fiddly and I'd prefer to fix this the correct way either with the machine or with fixing our testing code.

I've created an application, applied for the multicast permissioning, it was granted to my bundleID and therefore my application. I've since come out with new versions of the same app, but now multicast entitlement is no longer provisioned. What must I check to identify where the problem exists? I can provide any details needed to troubleshoot.

TL;DR: How does one use DNSServiceReconfirmRecord() to invalidate mDNS state of a device that's gone offline? I'm using the DNSServiceDiscovery API (dns_sd.h) for a local P2P service. The problem I'm trying to solve is how to deal with a peer that abruptly loses connectivity, i.e. by turning off WiFi or simply by moving out of range or otherwise losing connectivity. In this situation there is of course no notification that the peer device has gone offline; it simply stops sending any packets. After my own timeout mechanism determines the peer is not responding, I mark it as offline in my own data structures. The problem is how to discover when/if it comes back online later. My DNSServiceBrowse callback won't be invoked because mDNS doesn't know the device went offline in the first place. I am trying to use DNSServiceReconfirmRecord, which appears to be for exactly this use case -- "Instruct the daemon to verify the validity of a resource record that appears to be out of date (e.g. because TCP connection to a service's target failed.)" However my attempts always return a BadReference error (-65541). The function requires me to pass a DNS record, and the only one I know is the TXT record; perhaps it needs a different one? Which, and how would I get it? Thanks!

Hello, is there a way to get MCC/MNC carrier codes on iOS? I'm also wondering if there's a private API. I want to obtain network information while I am abroad to determine the country of residence.