For years our iOS apps have experienced a networking problem, which blocks them connecting to our servers via their API endpoint domains. How can we recover after the scenario described below? Using 3rd party error logging solutions, which have different endpoint domains, we can record the error: NSUnderlyingError": Error Domain=kCFErrorDomainCFNetwork Code=-1200 "(null)" UserInfo={_kCFStreamPropertySSLClientCertificateState=0, _kCFNetworkCFStreamSSLErrorOriginalValue=-9816, _kCFStreamErrorDomainKey=3, _kCFStreamErrorCodeKey=-9816, _NSURLErrorNWPathKey=satisfied (Path is satisfied), viable, interface: pdp_ip0[lte], ipv4, dns, expensive, uses cell}, "_NSURLErrorFailingURLSessionTaskErrorKey": LocalDataTask <DEDBFA4D-810D-4438-A6A0-95E3B9668B9E>.<308>, "_kCFStreamErrorDomainKey": 3, "_NSURLErrorRelatedURLSessionTaskErrorKey": <__NSSingleObjectArrayI 0x301f82e60>( LocalDataTask <DEDBFA4D-810D-4438-A6A0-95E3B9668B9E>.<308> ) "NSLocalizedDescription": An SSL error has occurred and a secure connection to the server cannot be made., "NSLocalizedRecoverySuggestion": Would you like to connect to the server anyway? -9816 is the "server closed session with no notification" error based on comments in CoreFoundation source files. Subsequent API endpoint calls to the same domain return the same error. The SSL error occurs most prevalently after a server outage. However, despite our best efforts, we have been unable to replicate triggering the problem for development purposes via experiments with our server. When the error occurs the users report that: Fully closing (i.e. not just sending to background) and reopening the app does NOT clear connectivity to our server being blocked. Problem seems more prevalent when using mobile/cell data. Switching from mobile/cell data to WIFI resolves the connection problem and then switching back to mobile/cell data shows the problem again. So the underlying problem is not cleared. All other apps on the same device and mobile/cell data or WIFI connection, like Safari, have no problems connecting to the Internet. Deleting and reinstalling, or updating (when an update is available) resolves the problem. Or after waiting a few days the problem seems to resolve itself. The last two point above suggest that something is persisted/cached in the app preventing it from connecting properly with subsequent network attempts. Notes: We have one shared instance of the URLSession in the app for its networking because we are aware of the perils of multiple URLSession instances. We recently added conditions to call the URLSession await reset() method when detecting the SLL errors before repeating the request. It is debatable whether this reduces the problem as we still see logged cases with the subsequent requests hitting the same -9816 error. URLSession configuration: let config = URLSessionConfiguration.default config.timeoutIntervalForResource = 22 config.timeoutIntervalForRequest = 20 config.requestCachePolicy = .reloadIgnoringLocalCacheData config.urlCache = nil

I am pretty sure iOS 13.4 (beta and later) did support Coded PHY (Long Range). Tested devices are iPhone SE2 and iPhone 11 Pro. However, it seems iOS 14 removed the support of Coded PHY, accidentally or on purpose, I don't know? The same PHY update request returns "1M PHY" in iOS 14, but "Coded PHY" in iOS 13 (13.4 beta and later). Anyone knows why? Samson

Hi All, I am currently working on a Network Extension App for MacOS using 3 types of extensions provided by Apple's Network Extension Framework. Content Filter, App Proxy (Want to get/capture/log all HTTP/HTTPS traffic), DNS Proxy (Want to get/capture/log all DNS records). Later parse into human readable format. Is my selection of network extension types correct for the intended logs I need? I am able to run with one extension: Main App(Xcode Target1) <-> Content Filter Extension. Here there is a singleton class IPCConnection between App(ViewController.swift) which is working fine with NEMachServiceName from Info.plist of ContentFilter Extension(Xcode Target2) However, when I add an App Proxy extension as a new Xcode Target3, I think the App and extension's communication getting messed up and App not getting started/Crashing. Here, In the same Main App, I am adding new separate IPCConnection for this extension. Here is the project organization/folder structure. MyNetworkExtension ├──MyNetworkExtension(Xcode Target1) │ ├── AppDelegate.swift │ ├── Assets.xcassets │ ├── Info.plist │ ├── MyNetworkExtension.entitlement │ | ── Main │ |-----ViewController.swift │ └── Base.lproj │ └── Main.storyboard ├── ContentFilterExtension(Xcode Target2) │ ├── ContentFilterExtension.entitlement │ │ ├── FilterDataProvider.swift │ │ ├── Info.plist │ │ ├── IPCConnection.swift │ │ └── main.swift ├── AppProxyProviderExtension(Xcode Target3) │ ├── AppProxyProviderExtension.entitlement │ │ ├── AppProxyIPCConnection.swift │ │ ├── AppProxyProvider.swift │ │ ├── Info.plist │ │ └── main.swift └── Frameworks ├── libbsm.tbd └── NetworkExtension.framework Is my Approach for creating a single Network Extension App with Multiple extensions correct or is there any better approach of project organization that will make future modifications/working easier and makes the maintenance better? I want to keep the logic for each extension separate while having the same, single Main App that manages everything(installing, activating, managing identifiers, extensions, etc). What's the best approach to establish a Communication from MainApp to each extension separately, without affecting one another? Is it good idea to establish 3 separate IPC Connections(each is a singleton class) for each extension? Are there any suggestions you can provide that relates to my use case of capturing all the network traffic logs(including HTTP/HTTPS, DNS Records, etc), especially on App to Extension Communication, where my app unable to keep multiple IPC Connections and maintain them separately? I've been working on it for a while, and still unable to make the Network Extension App work with multiple extensions(each as a new Xcode target). Main App with single extension is working fine, but if I add new extension, App getting crashed. I suspect it's due to XPC/IPC connection things! I really appreciate any support on this either directly or by any suggestions/resources that will help me get better understand and make some progress. Please reach out if in case any clarifications or specific information that's needed to better understand my questions. Thank you very much

Hello Apple Support Team, We are experiencing a performance issue with HTTP/3 in our iOS application during testing. Problem Description: Network requests using HTTP/3 are significantly slower than expected. This issue occurs on both Wi-Fi and 4G networks, with both IPv4 and IPv6. The same setup worked correctly in an earlier experiment. Key Observations: The slowdown disappears when the device uses: · A personal hotspot. · Network Link Conditioner (with no limitations applied). · Internet sharing from a MacBook via USB (where traffic was also inspected with Wireshark without issues). The problem is specific to HTTP/3 and does not occur with HTTP/2. The issue is reproducible on iOS 15, 18.7, and the latest iOS 26 beta. HTTP/3 is confirmed to be active (via assumeHttp3Capable and Alt-Svc header). Crucially, the same backend endpoint works with normal performance on Android devices and using curl with HTTP/3 support from the same network. I've checked the CFNetwork logs in the Console but haven't found any suspicious errors or obvious clues that explain the slowdown. We are using a standard URLSession with basic configuration. Attempted to collect qlog diagnostics by setting the QUIC_LOG_DIRECTORY=~/ tmp environment variable, but the logs were not generated. Question: What could cause HTTP/3 performance to improve only when the device is connected through a hotspot, unrestricted Network Link Conditioner, or USB-tethered connection? The fact that Android and curl work correctly points to an issue specific to the iOS network stack. Are there known conditions or policies (e.g., related to network interface handling, QoS, or specific packet processing) that could lead to this behavior? Additionally, why might the qlog environment variable fail to produce logs, and are there other ways to obtain detailed HTTP/3 diagnostic information from iOS? Any guidance on further diagnostic steps or specific system logs to examine would be greatly appreciated. Thank you for your assistance.

When setting up a packet tunnel with a profile that has includeAllNetworks set to true, we seemingly cannot send any traffic inside the tunnel using any kind of an API. We've tried using BSD sockets, as we ping a host only reachable within the tunnel to establish whether we have connectivity - this does not work. When using NWConnection from the Network framework and specifying the required interface via virtualInterface from the packet tunnel, the connection state never reaches ready. Our interim solution is to, as ridiculous as it sounds, include a whole userspace networking stack so we can produce valid TCP packets just to send into our own tunnel. We require a TCP connection within our own tunnel to do some configuration during tunnel setup. Is there no better solution?

Hello, I've been experimenting with the new NEURLFilter API and so far the results are kind of strange. SimpleURLFilter sample contains a bloom filter that seems to be built from this dataset in pir-service-example. I was able to run SimpleURLFilter sample and configure it to use PIRService from the example repo. I also observed the requests that iOS has been sending: requesting config and then sending /queries request. What I haven't seen is any .deny verdict for any URL. Even when calling NEURLFilter.verdict(for: url) directly I cannot see a .deny verdict. Is there anything wrong with the sample or is there a known issue with NEURLFilter in the current beta (beta 8) that prevents it from working?

I am using a URLSessionWebSocketTask. When trying to receive messages while the app is backgrounded, the receive() method fails with an NSError where the domain is NSPOSIXErrorDomain and the code is ECONNABORTED. That behavior is good. However, when this happens, the URLSessionWebSocketTask reports a closeCode of invalid, which is supposed to denote that the connection is still open. However, the connection state property is reporting completed. I feel that the closeCode property should be reporting something like abnormalClosure in this case. Either way, this seems like a bug or the documentation is incorrect.

I have added a Network Extension to my iOS project to use the WireGuard library. Everything was working fine up to Xcode 16, but after updating, I’m facing a build issue. The build fails with the following error: No such file or directory: '@rpath/WireGuardNetworkExtensioniOS.debug.dylib' I haven’t explicitly added any .dylib to my project. The Network Extension target builds and runs fine on Xcode 16.

Hi, Our project is a MacOS SwiftUI GUI application that bundles a (Sandboxed) System Network Extension, signed with a Developer ID certificate for distribution outside of the app store. The system network extension is used to write a packet tunnel provider (NEPacketTunnelProvider), as our project requires the creation of a TUN device. In order for our System VPN to function, it must reach out to a (self-hosted) server (i.e. to discover a list of peers). Being self-hosted, this server is typically not accessible via the public web, and may only be accessible from within a VPN (such as those also implemented using NEPacketTunnelProvider, e.g. Tailscale, Cloudflare WARP). What we've discovered is that the networking code of the System Network Extension process does not attempt to use the other VPN network interfaces (utunX) on the system. In practice, this means requests to IPs and hostnames that should be routed to those interfaces time out. Identical requests made outside of the Network System Extension process use those interfaces and succeed. The simplest example is where we create a URLSession.downloadTask for a resource on the server. A more complicated example is where we execute a Go .dylib that continues to communicate with that server. Both types of requests time out. Two noteworthy logs appear when packets fail to send, both from the kernel 'process': cfil_hash_entry_log:6088 <CFIL: Error: sosend_reinject() failed>: [30685 com.coder.Coder-Desktop.VPN] <UDP(17) out so b795d11aca7c26bf 57728068503033955 57728068503033955 age 0> lport 3001 fport 3001 laddr 100.108.7.40 faddr 100.112.177.88 hash 58B15863 cfil_service_inject_queue:4472 CFIL: sosend() failed 49 I also wrote some test code that probes using a UDP NWConnection and NWPath availableInterfaces. When run from the GUI App, multiple interfaces are returned, including the one that routes the address, utun5. When ran from within the sysex, only en0 is returned. I understand routing a VPN through another is unconventional, but we unfortunately do need this functionality one way or another. Is there any way to modify which interfaces are exposed to the sysex? Additionally, are these limitations of networking within a Network System Extension documented anywhere? Do you have any ideas why this specific limitation might exist?

Recently, my application was having trouble sending udp messages after it was reinstalled. The cause of the problem was initially that I did not grant local network permissions when I reinstalled, I was aware of the problem, so udp worked fine after I granted permissions. However, the next time I repeat the previous operation, I also do not grant local network permissions, and then turn it back on in the Settings, and udp does not work properly (no messages can be sent, the system version and code have not changed). Fortunately, udp worked after rebooting the phone, and more importantly, I was able to repeat the problem many times. So I want to know if the process between when I re-uninstall the app and deny local network permissions, and when I turn it back on in Settings, is that permissions have been granted normally, and not fake, and not required a reboot to reset something for udp to take effect. I'm not sure if it's the system, or if it's a similar situation as described here, hopefully that will help me find out

I've had a Unreal Engine project that uses libwebsocket to make a websocket connection with SSL to a server. Recently I made a build using Unreal Engine 5.4.4 on MacOS Sequoia 15.5 and XCode 16.4 and for some reason the websocket connection now fails because it can't get the local issuer certificate. It fails to access the root certificate store on my device (Even though, running the project in the Unreal Editor works fine, it's only when making a packaged build with XCode that it breaks) I am not sure why this is suddenly happening now. If I run it in the Unreal editor on my macOS it works fine and connects. But when I make a packaged build which uses XCode to build, it can't get the local issuer certificate. I tried different code signing options, such as sign to run locally or just using sign automatically with a valid team, but I'm not sure if code signing is the cause of this issue or not. This app is only for development and not meant to be published, so that's why I had been using sign to run locally, and that used to work fine but not anymore. Any guidance would be appreciated, also any information on what may have changed that now causes this certificate issue to happen. I know Apple made changes and has made notarizing MacOS apps mandatory, but I'm not sure if that also means a non-notarized app will now no longer have access to the root certificate store of a device, in my research I haven't found anything about that specifically, but I'm wondering if any Apple engineers might know something about this that hasn't been put out publicly.

Hi Team, OS is prompting for local network permission for our application which runs as root level daemon. As per the our analysis, it looks like it is prompting from our own library which is trying to get network info ' using /usr/sbin/system_profiler with "-xml -detailLevel basic SPNetworkDataType" and then trying to iterate to find DNS.ServerAddresses for each item. Then using [NSHost hostWithAddress:IPAddress];(When this library is not linked to the app then there is no prompt, so most likely this is the code that is resulting in the prompt). Is this expected ? . Is there any other way that we can get DNS host name without being prompted for local network permission on mac OS 15

Howdy, I've been developing a packet tunnel extension meant to run on iOS and MacOS. For development I'm using xcodegen + xcodebuild to assemble a bunch of swift and rust code together. I'm moving from direct TUN device management on Mac to shipping a Network Extension (appex). With that move I noticed that on some mac laptops NE fails to start completely, whilst on others everything works fine. I'm using CODE_SIGN_STYLE: Automatic, Apple IDs are within the same team, all devices are registered as dev devices. Signing dev certificates, managed by xcode. Some suspicious logs: (NetworkExtension) [com.apple.networkextension:] Signature check failed: code failed to satisfy specified code requirement(s) ... (NetworkExtension) [com.apple.networkextension:] Provider is not signed with a Developer ID certificate What could be the issue? Where those inconsistencies across devices might come from?

We've received several reports of a new bug while setting up our products with WAC. The Accessory Setup UI appears with a blank network selected and the message 'This accessory will be set up to join "(null)".' at top. The user can tap "Show Other Networks..." to select another network, but this experience is very confusing. Why does this UI present a choice that is known to be invalid when other valid choices exist? I've captured a screenshot and sysdiagnose from this case. In most cases this problem happens only intermittently, but I can reproduce it consistently by disconnecting my iPhone from any WiFi network (WiFi remains enabled). My suggestion for a better user experience is that this UI should select the default network according to these rules: The network to which iPhone is currently connected. Any network which is in the known/my list for this iPhone Any valid network I believe rule #1 is the existing behavior, but applying rules #2 and #3 as fallbacks would be an improvement. Is there anything I can change in my iOS code or in my accessory's WAC server to improve this experience?

My company has a server that supports ticket-based TLS session resumption (per RFC 5077). We have done Wireshark captures that show that our iOS client app, which uses URLSession for REST and WebSocket connections to the server, is not sending the TLS "session_ticket" extension in the Client Hello package that necessary to enable ticket-based resumption with the server. Is it expected that URLSession does not support ticket-based TLS session resumption? If "yes", is there any way to tell URLSession to enable ticket-based session resumption? the lower-level API set_protocol_options_set_tls_tickets_enabled() hints that the overall TLS / HTTP stack on IOS does support ticket-based resumption, but I can't see how to use that low-level API with URLSession. I can provide (lots) more technical details if necessary, but hopefully this is enough context to determine whether ticket-based TLS resumption is supported with URLSession. Any tips / clarifications would be greatly appreciated.

Eager to see the Wi-Fi Aware communication between iPhone (iOS 26) and an Android device, I tried iOS 26 beta on my iPhone16. and tried below code snippet from provided example at https://developer.apple.com/documentation/wifiaware/building-peer-to-peer-apps. Idea is to first verify discovery of Android WiFiAware service on iOS. extension WAPublishableService { public static var simulationService: WAPublishableService { allServices[simulationServiceName]! } } extension WASubscribableService { public static var simulationService: WASubscribableService { allServices[simulationServiceName]! } } struct ContentView: View { @State private var showingDevicePicker = false @State private var pairedDevices: [WAPairedDevice] = [] // To hold discovered/paired devices var body: some View { VStack { Button("Discover Devices") { showingDevicePicker = true // Trigger the device picker presentation } .sheet(isPresented: $showingDevicePicker) { DevicePicker(.wifiAware(.connecting(to: .selected([]), from: .simulationService))) { endpoint in print("Paired Endpoint: \(endpoint)") } label: { Image(systemName: "plus") Text("Add Device") } fallback: { Image(systemName: "xmark.circle") Text("Unavailable") } } List(pairedDevices) { device in Text(device.name ?? "Unknown Device") } } } } With suggested entitlement of WiFiAware and info.plist of service info. Then I had Android device with WIFiAware service publishing service (service name set '_sat-simulation._udp') from this app https://github.com/anagramrice/NAN. But above iOS app is unable to find the service published from android device. Am I missing something? Note: the above Android-NAN app seems to be working fine between Android to Another Android.

In our iOS application, we need to list available WiFi networks so that users can select one for device configuration. Here's the workflow: Initially, the hardware device acts as a WiFi Access Point (AP). The app should scan for nearby WiFi networks to detect the device's AP. The app connects temporarily to this AP and sends the selected WiFi credentials to the device. The device then connects to the selected WiFi network and stops broadcasting its AP. Is this flow achievable on iOS? We understand that Apple restricts access to WiFi scanning APIs — are there any supported methods (e.g., using NEHotspotHelper) or entitlements (such as MFi) that could enable this?

Greetings, I would like to understand this URLCache behavior for two different requests to the same end point but with a different header value. Here is a code with comment explaining the behavior. // Create a request to for a url. let url = URL(string: "https://&lt;my url&gt;?f=json")! var request = URLRequest(url: url) // Set custom header with a value. request.setValue("myvalue", forHTTPHeaderField: "CustomField") // Send request to get the response. let (data, response) = try await URLSession.shared.data(for: request) print("data: \(String(describing: String(data: data, encoding: .utf8)))") print("response: \(response)") // Create second request to the same url but with different value of custom header field. var request2 = URLRequest(url: url) request2.setValue("newvalue", forHTTPHeaderField: "CustomField") // Check the URL cache for second request and it returns the response // of the first request even though the second request has different header value. let cachedResponse = URLCache.shared.cachedResponse(for: request2) print("cachedResponse: \(cachedResponse?.response)") Is this a bug in URLCache that request headers are not matched while returning the response? Is this an expected behavior? If yes, why?

Hello, I'm trying to build the sample app from Building peer-to-peer apps that demonstrates Wi-Fi Aware. Upon downloading the example source code, opening it in Xcode 26.0 beta, and building the app, the compiler fails with: DeviceDiscoveryPairingView.swift:8:8 No such module 'DeviceDiscoveryUI' Is this a known issue? I know that DeviceDiscoveryUI was previously only a tvOS capability. Thanks

My application needs local network access. When it is started for the first time, the user gets a prompt to enable local network access (as expected). The application is then shown as enabled in Privacy & Security / Local Network and local network access is working. If macOS is then shutdown and restarted, local network access is blocked for the application even though it is still shown as enabled in Privacy & Security / Local Network. Local network access can be restored either by toggling permission off and on in Privacy & Security / Local Network or by disabling and enabling Wi-Fi. This behaviour is consistent on Sequoia 15.1. It happens sometimes on 15.0 and 15.0.1 but not every time. Is my application doing something wrong or is this a Sequoia issue? If it is a Sequoia issue, is there some change I can make to my application to work around it?