Hello Everyone, I am currently using macOS 15.5 and XCode 16.4. I am using the following code to send/receive multicast packets on multicast group ff02::1 and port 49153 using Apple NF's NWConnectionGroup. import Network import Foundation // Creating a mutlicast group endpoint let multicastIPv6GroupEndpoint: NWEndpoint = NWEndpoint.hostPort(host: NWEndpoint.Host.ipv6(IPv6Address("ff02::1")!), port: NWEndpoint.Port("49153")!) do { let multicastGroupDescriptor: NWMulticastGroup = try NWMulticastGroup (for: [multicastIPv6GroupEndpoint]) let multicastConnectionGroupDescriptor = NWConnectionGroup (with: multicastGroupDescriptor, using: .udp) multicastConnectionGroupDescriptor.stateUpdateHandler = { state in print ("🕰️ Connection Group state: \(state)") if state == .ready { multicastConnectionGroupDescriptor.send (content: "👋🏻 Hello from the Mac 💻".data (using: .utf8)) { err in print ("➡️ Now, I am trying to send some messages.") if let err = err { print ("💥 Error sending multicast message: \(err)") } else { print ("🌚 Initial multicast message sent") } } } } multicastConnectionGroupDescriptor.setReceiveHandler { message, content, isComplete in if let content = content, let messageString = String (data: content, encoding: .utf8) { print ("⬅️ Received message: \(messageString)") } } multicastConnectionGroupDescriptor.start (queue: .global()) } catch { print ("💥 Error while creating Multicast Group: \(error)") } RunLoop.main.run() I am able to successfully create a NWConnectionGroup without any warnings/errors. The issue occurs when the stateUpdateHandler's callback gets invoked. It first gives me this warning: nw_listener_socket_inbox_create_socket IPV6_LEAVE_GROUP ff02::1.49153 failed [49: Can't assign requested address But then it shows me that the state is ready: 🕰️ Connection Group state: ready After this, when the send is performed, it gives me a bunch of errros: nw_endpoint_flow_failed_with_error [C1 ff02::1.49153 waiting parent-flow (unsatisfied (Local network prohibited), interface: en0[802.11], ipv4, ipv6, uses wifi)] already failing, returning nw_socket_connect [C1:1] connectx(7, [srcif=0, srcaddr=::.62838, dstaddr=ff02::1.49153], SAE_ASSOCID_ANY, 0, NULL, 0, NULL, SAE_CONNID_ANY) failed: [48: Address already in use] nw_socket_connect [C1:1] connectx failed (fd 7) [48: Address already in use] nw_socket_connect connectx failed [48: Address already in use] nw_endpoint_flow_failed_with_error [C1 ff02::1.49153 in_progress socket-flow (satisfied (Path is satisfied), interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] already failing, returning There is no other background process running on the same port. I tried using different ports as well as multicast groups but the same error persists. The same code works fine for an IPv4 multicast group. I have following questions: Why am I getting these errors specifically for IPv6 multicast group but not for IPv4 multicast group? Are there any configurations that needed to be done in order to get this working?

I have written an App which extracts data, over WiFi, from an instrument that creates its own WiFi Hotspot. The instrument provides no internet connection. The iPad version of this App is connects fine and is assigned an IP address by DHCP server running on a MicroChip RN171 wifi module. iOS assigns an obscure IP address on a completely different subnet. I understand this is iOS' way of "Complaining" that is wasn't assigned an IP address. Consequently in the case of the iPhone I am forced to manually assign an IP address for the iPhone, the mask and the gateway. Only then is the connection successful. Anyone know why the iPhone won't talk DHCP to a WiFi module not connected to the internet? Are there perhaps some parameters that I need to adjust on either the iPhone or WiFi module?

Hi! My project has the Local Push Connectivity entitlement for a feature we have requiring us to send low-latency critical notifications over a local, private Wi-Fi network. We have our NEAppPushProvider creating a SSE connection using the Network framework with our hardware running a server. The server sends a keep-alive message every second. On an iPhone 16 with iOS 18+, the connection is reliable and remains stable for hours, regardless of whether the iOS app is in the foreground, background, or killed. One of our QA engineers has been testing on an iPhone 13 running iOS 16, and has notice shortly after locking the phone, specifically when not connected to power the device seems to turn off the Wi-Fi radio. So when the server sends a notification, it is not received. About 30s later, it seems to be back on. This happens on regular intervals. When looking at our log data, the provider does seem to be getting stopped, then restarted shortly after. The reason code is NEProviderStopReasonNoNetworkAvailable, which further validates that the network is getting dropped by the device in regular intervals. My questions are: Were there possibly silent changes to the framework between iOS versions that could be the reason we're seeing inconsistent behavior? Is there a connection type we could use, instead of SSE, that would prevent the device from disconnecting and reconnecting to the Wi-Fi network? Is there an alternative approach to allow us to maintain a persistent network connection with the extension or app?

We have observed an internet access issue after the device enters idle mode on iOS 26 beta 9. Although the Ivanti Secure Access Client appears connected, users are unable to access any resources (internet or intranet) after unlocking the device from idle. When we check the log socket connection looks not disrupted, packets are tunnelled but no resource access. Split tunnel enabled and proxy PAC configured. This was observed on both iOS and iPadOS 26 beta. Steps to reproduce: Connecting to the internet, launching the Ivanti client, locking the device, and then unlocking it after a brief period of idle. The issue occurs when the VPN remains connected but no resources are accessible.

Hello eveybody,Currently I'm working on an app which connects to a device. During testing I encounter an internal error of NEHotspotConfigurationErrorDomain. See the log snippet:Domain=NEHotspotConfigurationErrorDomain Code=8 "internal error." UserInfo={NSLocalizedDescription=internal error.}This error appears randomly. In one day I encountered it three times. The only solution I can think of is catching this error somehow and then telling the user to restart the device.After this error appears, the wifi functionality of iOS in all third party apps seems to be broken. Only restarting helps as far as I know. Also there seems to be nothing we as app developers can do about it. Therefor I wonder if there is some way to prevent this error somehow? The only solution I can think of is catching this error somehow and then telling the user to restart the device.Also since there is not much information about this error on the web, it would be really nice if someone can clarify whats going on with this error.Regards.

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?

I am in the middle of investigating an issue arising in the call to setsockopt syscall where it returns an undocumented and unexpected errno. As part of that, I'm looking for a way to list any socket content filters or any such extensions are in play on the system where this happens. To do that, I ran: systemextensionsctl list That retuns the following output: 0 extension(s) which seems to indicate there's no filters or extensions in play. However, when I do: netstat -s among other things, it shows: net_api: 2 interface filters currently attached 2 interface filters currently attached by OS 2 interface filters attached since boot 2 interface filters attached since boot by OS ... 4 socket filters currently attached 4 socket filters currently attached by OS 4 socket filters attached since boot 4 socket filters attached since boot by OS What would be the right command/tool/options that I could use to list all the socket filters/extensions (and their details) that are in use and applicable when a call to setsockopt is made from an application on that system? Edit: This is on a macosx-aarch64 with various different OS versions - 13.6.7, 14.3.1 and even 14.4.1.

Hello, Our users are seeing random crashes in our packet filter system extension on macOS. Any help pointing me in the right direction to either avoid the issue or fix it would be greatly appreciated. Attached is the crash log. Thank you. packetfilter.crash Crashed Thread: 2 Dispatch queue: com.apple.network.connections Exception Type: EXC_BAD_ACCESS (SIGBUS) Exception Codes: KERN_PROTECTION_FAILURE at 0x0000000112918700 Exception Note: EXC_CORPSE_NOTIFY Termination Signal: Bus error: 10 Termination Reason: Namespace SIGNAL, Code 0xa Terminating Process: exc handler [40687] ... Thread 2 Crashed:: Dispatch queue: com.apple.network.connections 0 libsystem_kernel.dylib 0x00007fff2089b46e os_channel_get_next_slot + 230 1 com.apple.NetworkExtension 0x00007fff2e2e2643 __40-[NEFilterPacketInterpose createChannel]_block_invoke + 560 2 libdispatch.dylib 0x00007fff20718806 _dispatch_client_callout + 8 3 libdispatch.dylib 0x00007fff2071b1b0 _dispatch_continuation_pop + 423 4 libdispatch.dylib 0x00007fff2072b564 _dispatch_source_invoke + 2061 5 libdispatch.dylib 0x00007fff20720318 _dispatch_workloop_invoke + 1784 6 libdispatch.dylib 0x00007fff20728c0d _dispatch_workloop_worker_thread + 811 7 libsystem_pthread.dylib 0x00007fff208bf45d _pthread_wqthread + 314 8 libsystem_pthread.dylib 0x00007fff208be42f start_wqthread + 15

I have a custom VPN app that uses NETunnelProviderManager to install a VPN Profile if one is not already installed. On previous iOS versions this would open the VPN Settings and ask for either the PIN, FaceID or TouchID and install the profile. With iOS 26 beta5 it opens the VPN Settings and stops. Is this a bug in iOS 26? Have there been changes to NETunnelProviderManager for iOS 26 that I'm not aware of? FYI we do the samething on macOS 26 beta5 and that works as expected.

I upgraded my Mac to Sequoia 15.4.1 an i hat to upgrade XCode to Version 16.3. I access a MQTT Broker by an sending an mosquitto_sub request to the Broker. Now its no longer possible the request fails i granted Network permission to my App

I have an app that has been using the following code to down load audio files: if let url = URL(string: episode.fetchPath()) { var request = URLRequest(url: url) request.httpMethod = "get" let task = session.downloadTask(with: request) And then the following completionHandler code: func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingTo location: URL) { try FileManager.default.moveItem(at: location, to: localUrl) In the spirit of modernization, I'm trying to update this code to use async await: var request = URLRequest(url: url) request.httpMethod = "get" let (data, response) = try await URLSession.shared.data(for: request) try data.write(to: localUrl, options: [.atomicWrite, .completeFileProtection]) Both these code paths use the same url value. Both return the same Data blobs (they return the same hash value) Unfortunately the second code path (using await) introduces a problem. When the audio is playing and the iPhone goes to sleep, after 15 seconds, the audio stops. This problem does not occur when running the first code (using the didFinish completion handler) Same data, stored in the same URL, but using different URLSession calls. I would like to use async/await and not have to experience the audio ending after just 15 seconds of the device screen being asleep. any guidance greatly appreciated.

When installing a new version the app while a tunnel is connected, seemingly the old packet tunnel process gets stopped but the new one does not come back up. Reportedly, a path monitor is reporting that the device has no connectivity. Is this the expected behavior? When installing an update from TestFlight or the App store, the packet tunnel instance from the old tunnel is stopped, but, due to the profile being on-demand and incldueAllNetworks, the path monitoring believes the device has no connectivity - so the new app is never downloaded. Is this the expected behavior? During development, the old packet tunnel gets stopped, the new app is installed, but the new packet tunnel is never started. To start it, the user has to toggle the VPN twice from the Settings app. The tunnel could be started from the VPN app too, if we chose to not take the path monitor into account, but then the user still needs to attempt to start the tunnel twice - it only works on the second try. As far as we can tell, the first time around, the packet tunnel never gets started, the app receives an update about NEVPNStatus being set to disconnecting yet NEVPNConnection does not throw. The behavior I was naively expecting was that the packet tunnel process would be stopped only when the new app is fully downloaded and when the update is installed, Are we doing something horribly wrong here?

Description Enterprise users are experiencing VPN resource access failures after upgrading to macOS Tahoe. Investigation indicates that configd (specifically IPMonitor) is incorrectly re-ranking network interfaces after a connectivity failure with probe server. This results in DNS queries routing through the physical network adapter (en0) instead of the VPN virtual adapter, even while the tunnel is active. This behaviour is not seen in previous macOS versions. Steps to Reproduce: Connect to an enterprise VPN (e.g., Ivanti Secure Access). Trigger a transient network condition where the Apple probe server is unreachable. For example make the DNS server down for 30 sec. Observe the system routing DNS queries for internal resources to the physical adapter. Expected Results The: VPN virtual interface should maintain its primary rank for enterprise DNS queries regardless of the physical adapter's probe status. Actual Results: IPMonitor detects an UplinkIssue, deprioritizes the VPN interface, and elevates the physical adapter to a higher priority rank. Technical Root Cause & Logs: The system logs show IPMonitor identifying an issue and modifying the interface priority at 16:03:54: IPMonitor Detection: The process identifies an inability to reach the Apple probe server and marks en0 with an advisory: Log snippet 2026-01-06 16:03:53.956399+0100 localhost configd[594]: [com.apple.SystemConfiguration:IPMonitor] configd[594] SetInterfaceAdvisory(en0) = UplinkIssue (2) reason='unable to reach probe server' Interface Re-ranking: Immediately following, IPMonitor recalculates the rank, placing the physical service ID at a higher priority (lower numerical rank) than the VPN service ID (net.pulsesecure...): Log snippet 2026-01-06 16:03:53.967935+0100 localhost configd[594]: [com.apple.SystemConfiguration:IPMonitor] 0. en0 serviceID=50CD9266-B097-4664-BFE6-7BAFCC5E9DC0 addr=192.168.0.128 rank=0x200000d 2026-01-06 16:03:53.967947+0100 localhost configd[594]: [com.apple.SystemConfiguration:IPMonitor] 1. en0 serviceID=net.pulsesecure.pulse.nc.main addr=192.168.0.128 rank=0x2ffffff 3.Physical adapter Is selected as Primary Interface: 2026-01-06 16:03:53.968145+0100 localhost configd[594]: [com.apple.SystemConfiguration:IPMonitor] 50CD9266-B097-4664-BFE6-7BAFCC5E9DC0 is the new primary IPv4 configd[594]: 50CD9266-B097-4664-BFE6-7BAFCC5E9DC0 is the new primary DNS Packet Trace Evidence Wireshark confirms that DNS queries for enterprise-specific DNS servers are being originated from the physical IP (192.168.0.128) instead of the virtual adapter: Time: 16:03:54.084 Source: 192.168.0.128 (Physical Adapter) Destination: 172.29.155.115 (Internal VPN DNS Server) Result: Connectivity Failure (Queries sent outside the tunnel)

Our product (rockhawk.ca) uses the Multipeer Connectivity framework for peer-to-peer communication between multiple iOS/iPadOS devices. My understanding is that MC framework communicates via three methods: 1) infrastructure wifi (i.e. multiple iOS/iPadOS devices are connected to the same wifi network), 2) peer-to-peer wifi, or 3) Bluetooth. In my experience, I don't believe I've seen MC use Bluetooth. With wifi turned off on the devices, and Bluetooth turned on, no connection is established. With wifi on and Bluetooth off, MC works and I presume either infrastructure wifi (if available) or peer-to-peer wifi are used. I'm trying to overcome two issues: Over time (since iOS 9.x), the radio transmit strength for MC over peer-to-peer wifi has decreased to the point that range is unacceptable for our use case. We need at least 150 feet range. We would like to extend this support to watchOS and the MC framework is not available. Regarding #1, I'd like to confirm that if infrastructure wifi is available, MC uses it. If infrastructure wifi is not available, MC uses peer-to-peer wifi. If this is true, then we can assure our customers that if infrastructure wifi is available at the venue, then with all devices connected to it, range will be adequate. If infrastructure wifi is not available at the venue, perhaps a mobile wifi router (battery operated) could be set up, devices connected to it, then range would be adequate. We are about to test this. Reasonable? Can we be assured that if infrastructure wifi is available, MC uses it? Regarding #2, given we are targeting minimum watchOS 7.0, would the available networking APIs and frameworks be adequate to implement our own equivalent of the MC framework so our app on iOS/iPadOS and watchOS devices could communicate? How much work? Where would I start? I'm new to implementing networking but experienced in using the MC framework. I'm assuming that I would write the networking code to use infrastructure wifi to achieve acceptable range. Many thanks! Tim

I want to configure one aspect of my networking configuration (the QUIC keepalive interval). This only seems to be configurable via Network.framework’s nw_quic_set_keepalive_interval. Is there any way to apply this to a URLSession? Or do I need to implement the whole connection management myself using Network.framework?

Hi, I am having a ton of issues with the new multicast/network entitlements requirements on MacOS. Basically, since my app didn't request these new entitlements until recently, if the app had been installed without these permissions enabled, it will not pick up the new permissions once they are enabled. The only options I had were to create a new user, and install the app under the new user, which works, but is not a real solution for users. This is really problematic, as there is no way currently to remove or change these network permissions once they are established. Is there a way to fix this? Or some other workarounds I am missing? Thanks Also via the documentation: TN3179: Understanding local network privacy | Apple Developer Documentation "There's no guarantee that it'll actually trigger the alert” And "On macOS there’s no way to reset your program’s Local Network privilege to the undetermined state (FB14944392). One alternative is to run your program in a virtual machine (VM). To retest, restore the VM from a snapshot taken before you installed your program.”

When I try to implement the new Background Task options in the same way as they show in the WWDC video (on watchOS) likes this: let config = URLSessionConfiguration.background(withIdentifier: "SESSION_ID") config.sessionSendsLaunchEvents = true let session = URLSession(configuration: config) let response = await withTaskCancellationHandler {       try? await session.data(for: request) } onCancel: {       let task = session.downloadTask(with: request))       task.resume() } I'm receiving the following error: Terminating app due to uncaught exception 'NSGenericException', reason: 'Completion handler blocks are not supported in background sessions. Use a delegate instead.' Did I forget something?

I'm working on two Swift applications which are using QUIC in Network.framework for communication, one serve as the listener (server) and the other serve as the client so that they can exchange data, both the server and the client app are running under the same LAN, the problem I met is that when client try to connect to the server, the connection will fail due to boring SSL, couple questions: Since both the server app and client app are running under the same LAN, do they need TLS certificate? If it does, will self-signed certificate P12 work? I might distribute the app in App Store or in signed/notarized dmg or pkg to our users. If I need a public certificate and self signed wouldn't work, since they are just pair of apps w/o fixed dns domain etc, Is there any public certificate only for standalone application, not for the fixed web domain?

I have an Xcode app where currently txt files in the project display text data as a list. I can search through the lists and have buttons that will swap between different lists of information that you can look through. The next task is I have URL connections to docx files on a SharePoint site. I am trying to use an URLsession function to connect to the URL links to download the documents to the document directory then have the application read the doc information to then be displayed as the txt info would. The idea is that the docx files are a type of online update version of the data. So when the app is used and on wifi, the app can update the list data with the docx files. I have code set up that should access the URL files but I am struggling to figure out how to read the data and access from this Documents directory. I have been looking online and so far I am at a loss on where to go here. If anyone can help or provide some insight I would greatly appreciate it. I can try and provide code samples to help explain things if that is needed.

We have an old iOS app and an old camera that connects using Wi-Fi either using an access point or Ad Hoc network, e.g., iPhone/iPad connects to the camera's Wi-Fi directly... How it works (old legacy app/system, which cannot be redesigned): Camera is configured to Ad Hoc Wi-Fi network (insecure TCP). iPhone connects to this insecure Wi-Fi. Camera uses Bonjour service to broadcast its IP address. App reads in IP address and begin to send messages to the camera using NSMutableURLRequest, etc. All this works fine for iOS 17. But in iOS 18 step 4 stopped working. App simply doesn't get any responses! We believe we have configured ATS properly (App Store version): In panic we have also tried this in Test Flight version: The latter actually seemed to make a difference when running the app on macOS Apple Silicon. But on iOS it didn't seem to make any difference. Occasionally, I was lucky to get connection on on iPhone 16 Pro with iOS 18. But for the 'many' iPads I have tried I couldn't. I also tried to install CFNetwork profile and look at the logs but I believe I just got timeout on the requests. Questions: Why it iOS 18 different? Bonjour works fine, but NSSURLRequests doesn't Do we configure ATS correctly for this scenario? What should I look for in the Console log when CFNetwork profile is installed? Should I file a TSI? Thanks! :)