I've implemented a custom system extension VPN for macOS using Packet Tunnel Provider. The VPN is configured with on-demand, and a rule to always connect whenever there's traffic: onDemandRules = [NEOnDemandRuleConnect()] As for the tunnel's settings (at the Packet Tunnel Provider), I've configured a split tunnel, so some routes are excluded from the tunnel. Now I have the following scenario: The VPN is connected The Mac enters sleep The sleep() function is called (at my Packet Tunnel Provider) The Mac briefly awakes to check emails/push notifications/etc. This traffic is excluded from the tunnel. What is the expected behavior here? Should the wake function be called because of the on-demand rule? Or should the VPN remain asleep because this traffic is excluded from the tunnel?

Context: We are using NWConnection for UDP and TCP Connections, and wanted to know the best way to keep the number of pending send completions in control to limit resource usage Questions: Is there a way to control the send rate, such that too many 'send pending completion' does not get queued. Say if I do a ‘extremely dense flurry of 10 million NWConnection.send’ will all go asynchronous without any complications? Or I would be informed once it reaches some threshold. Or no? And is it the responsibility of the application using NWConnection.send to limit the outstanding completion , as if they were beyond a certain limit, it would have an impact on outstanding and subsequent requests? If so – how would one know ‘what is supposed to be the limit’ at runtime? Is this a process level or system level limit. Will errors like EAGAIN and ETIMEOUT ever will be reported. In the test I simulated, where the TCP Server was made to not do receive, causing the 'socket send buffer' to become full on the sender side. On the sender side my send stopped getting complete, and became pending. Millions of sends were pending for long duration, hence wanted to know if we will ever get EAGAIN or ETIMEOUT.

Hi everyone, I developed an Android version of a VPN app built with Flutter using OpenVPN, and it works perfectly on Android. However, when porting it to iOS, I’ve encountered an issue: the app connects successfully but then automatically disconnects when tested via TestFlight. We’ve already added all the necessary network extensions. Despite this, we decided to submit the app to the App Store. It’s been five days now, and the app is still 'Waiting for Review.' Could anyone share their experience deploying and working on an iOS version of a VPN app? I’d really appreciate your insights!

It doesn’t seem like there’s any high level, first-party documentation on how to use what is the recommended API for executing networking logic that you otherwise wouldn’t use URLSession for; which is a lot of things. There’s a sample app, and docs on how to choose the right network API in general, but apparently no high level API docs for Network.framework itself. Am I missing something? How do people learn to use this? Know which classes to use? Know the various ways it can be configured?

Hello, we have noticed a crash in BigSur 11.7.10, 20G1427 libdispatch: Crashed Thread: 1 Dispatch queue: com.apple.network.connections Exception Type: EXC_BAD_INSTRUCTION (SIGILL) Exception Codes: 0x0000000000000001, 0x0000000000000000 Exception Note: EXC_CORPSE_NOTIFY Termination Signal: Illegal instruction: 4 Termination Reason: Namespace SIGNAL, Code 0x4 Terminating Process: exc handler [94088] Application Specific Information: BUG IN CLIENT OF LIBDISPATCH: Release of a suspended object Thread 0: 0 libsystem_kernel.dylib 0x00007fff20488aea __sigsuspend_nocancel + 10 1 libdispatch.dylib 0x00007fff2031f4e1 _dispatch_sigsuspend + 36 2 libdispatch.dylib 0x00007fff2031f4bd _dispatch_sig_thread + 53 Thread 1 Crashed:: Dispatch queue: com.apple.network.connections 0 libdispatch.dylib 0x00007fff2033cc35 _dispatch_queue_xref_dispose.cold.1 + 24 1 libdispatch.dylib 0x00007fff20313808 _dispatch_queue_xref_dispose + 50 2 libdispatch.dylib 0x00007fff2030e2eb -[OS_dispatch_source _xref_dispose] + 17 3 libnetwork.dylib 0x00007fff24255999 __nw_queue_context_create_source_block_invoke + 41 4 libdispatch.dylib 0x00007fff2030d623 _dispatch_call_block_and_release + 12 5 libdispatch.dylib 0x00007fff2030e806 _dispatch_client_callout + 8 6 libdispatch.dylib 0x00007fff203111b0 _dispatch_continuation_pop + 423 7 libdispatch.dylib 0x00007fff203211f4 _dispatch_source_invoke + 1181 8 libdispatch.dylib 0x00007fff20316318 _dispatch_workloop_invoke + 1784 9 libdispatch.dylib 0x00007fff2031ec0d _dispatch_workloop_worker_thread + 811 10 libsystem_pthread.dylib 0x00007fff204b545d _pthread_wqthread + 314 11 libsystem_pthread.dylib 0x00007fff204b442f start_wqthread + 15 I have seen similar crashes in the forum, but none from com.apple.network.connections queue. Should we raise a ticket or is this something that was fixed in newer OS versions? Thanks! Jakub

Hi everyone, I’m working with the DNSServiceGetAddrInfo API and came across the following statement in the documentation: If the call succeeds then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, and the query begins and will last indefinitely until the client terminates the query by passing this DNSServiceRef to DNSServiceRefDeallocate(_) I’m trying to understand exactly what this means in practice. Specifically, after receiving a response with kDNSServiceFlagsMoreComing, being set to 0 does it imply that the OS itself continues querying the DNS periodically or indefinitely, even after we've already received some results? Or does it only continue fetching additional results related to the initial query until we explicitly terminate it? Any clarification on the behavior of this query would be greatly appreciated! Thanks in advance!

With the new macOS 15, Apple introduced the new Local Network Privacy feature. This is causing issues for our customers as - even though they granted the required permission for our software - connections to a server in their local network are being blocked. The situation is not fixed by recent macOS updates. As far as I know, this issue exists for machines running on Apple Silicon. Systems running macOS versions (e.g. Sonoma) are not affected. Currently, the workaround is to re-enable the permission under Settings > Privacy & Security > Local Network. The list shows our application with an enabled checkbox. Users now have to de-select the box and then re-select it again for the application to work. They have to do this after each and every reboot of their system, which is slightly annoying (so at the moment we recommend to not upgrade macOS to Sequoia, if possible) I did some research and saw that other products are also affected by this bug. Is there a solution to this issue or any plans to fix it?

Hi all, I’m developing a watchOS app that uses a WebSocket API to process voice audio. However, I keep encountering this error when trying to establish the connection: nw_endpoint_flow_failed_with_error [C1 <server URL>:443 failed parent-flow (unsatisfied (Path was denied by NECP policy), interface: ipsec2, ipv4, ipv6, proxy)] already failing, returning I’ve read Technical Note TN3135, which outlines an exception for audio streaming apps. My app is an audio streaming app, and I’ve already added background audio mode to the app’s capabilities. However, I’m not sure what else is required to meet the exception described in TN3135. Questions How do I meet the exception outlined in TN3135 for WebSocket audio streaming on watchOS? Does NECP enforce additional restrictions even with background audio enabled, and how can I address this? Any guidance or examples of implementing WebSocket audio streaming on watchOS would be greatly appreciated. Thanks!

Dear Apple Team, I am facing an issue with UDP networking in my watchOS app for duplex audio streaming using NWConnection. I have already added the necessary capabilities, including background mode for audio, to ensure smooth operation. Issue Details: The UDP connection works fine on the simulator since it uses macOS networking and allows low-level access. However, on a real Apple Watch (running watchOS 10), the connection remains in a "waiting" state and fails with Error 50. I am aware of Technical Note TN3135 regarding low-level networking on watchOS, but even after following these guidelines, the issue persists. Questions: Does watchOS impose additional restrictions on UDP networking compared to iOS/macOS? Are there any specific entitlements or configurations required to allow UDP connections on a real Apple Watch? Is there a workaround or debugging method to get more insights into why the connection fails? I would appreciate any guidance or recommendations on resolving this issue.

I am unable to apply for Multicast Entitlement at https://developer.apple.com/contact/request/networking-multicast The reason for this is unclear. I have paid for a developer account and believe I'm up to date with all agreements.

I added a Content Filter to my app, and when running it in Xcode (Debug/Release), I get the expected permission prompt: "Would like to filter network content (Allow / Don't Allow)". However, when I install the app via TestFlight, this prompt doesn’t appear at all, and the feature doesn’t work. Is there a special configuration required for TestFlight? Has anyone encountered this issue before? Thanks!

When I used the iPhone 11 to scan the wifi connection, the system reported an error,   ‘’’ let config = NEHotspotConfiguration(ssid: name, passphrase: passwd, isWEP: false) let manager = NEHotspotConfigurationManager() manager.apply(config) { error in      } ’’’ NEHotspotConfigurationErrorDomain Code=8 “internal error.” , the only thins that fixes this issue it restarting the iPhone. What is the reason for this and how to solve it? Reference link: https://developer.apple.com/forums/thread/111638 https://cloud.tencent.com/developer/ask/sof/114654981

I am writing an app using Microsoft's MAUI platform. I am posting this here because that team wants me to make an xcode project to help determine an issue I am having. My MAUI app sends a broadcast packet on a UDP socket using address 255.255.255.255. This worked fine in iOS version 17.x. After upgrading my phone to iOS 18.x it stopped working. The error I get is "no route to host". The exact same code works fine on MacOS. It does not work on iPadOs 18. My question here is 3 fold: Did something specific change between iOS 17 and 18 that would cause a 'no route to host' error when sending a UDP broadcast packet? Can someone provide sample code to show me how to do this type of broadcast using Swift in Xcode for iOS? I read an article that said my app would need the com.apple.developer.networking.multicast entitlement in order to use boradcast functionality. This was introduced in iOS 14. Why did my app work fine in iOS 17 then? Is this what changed? Did this requirement use to be optional and is now required? I did get this entitlement from Apple and applied it to my provisioning profile and my app gave the same "no route to host" error. Why?

Hello. I would like to develop an application that sends SSH commands via my phone to the server. I know that applications of this type exist, but they are not suitable for my use as a blind person who uses a screen reader. I hope you can help me find libraries that will assist me in development, or ready-made, open-source projects that I can develop and modify if necessary. Thank you in advance.

Hi, I have been reviewing some previous discussions around networking in macOS, and I’d like to clarify my understanding of the differences between the kernel-space network stack and user-space network stack and validate this understanding based on the information shared in earlier threads. I’m also curious about how these differences impact macOS applications, particularly those requiring maintaining many simultaneous network connections. Understanding Kernel-Space vs User-Space Network Stack Kernel-Space Network Stack (BSD Sockets): The kernel-space networking stack refers to the traditional networking layer that runs in the kernel and handles network communication via BSD sockets. This stack is lower-level and interacts directly with the operating system's networking drivers and hardware. All network connections managed through this stack require a socket (essentially a file descriptor) to be opened, which places limits on the number of file descriptors that can be used (for example, the default 64K limit for sockets). The kernel network stack is traditionally used on macOS (and other UNIX-based systems) for networking tasks, such as when you use system APIs like BSD sockets. User-Space Network Stack (Network Framework): The user-space network stack in macOS (via the Network framework) allows applications to handle networking tasks without directly using the kernel. This provides more flexibility and performance benefits for certain types of network operations, as the networking stack is managed in user space rather than kernel space. This approach reduces overhead and allows more control over networking configurations. In theory, with user-space networking, the application wouldn't be bound by kernel-level socket limits, and it could handle many more simultaneous connections efficiently. In previous posts on that thread, Quinn mentioned that the Network framework in macOS can rely on the user-space stack (by default) for network operations, but there are still cases where macOS falls back to using the kernel stack (i.e., BSD sockets) under certain conditions. One key example is when the built-in firewall is enabled. This prevents user-space networking from functioning as expected, and the system defaults to using the kernel's BSD sockets for network communication. In the same discussion, it was also highlighted that NECP (Network Extension Control Plane) could place further limitations on user-space networking, and eventually, systems may run into issues like ENOSPC errors due to excessive simultaneous network flows. This suggests that while user-space networking can offer more flexibility, it's not immune to limits imposed by other system resources or configurations. Given the information above, I wanted to confirm: Is the above understanding correct and does the macOS Network framework still use the user-space networking stack in macOS 14 and beyond? Under what conditions would the system fall back to using the kernel stack (BSD sockets) instead of the user-space stack? For example, does enabling the firewall still disable user-space networking? What is the practical impact of this fallback on applications that require many simultaneous network connections? Specifically, are there any limitations like the 64K socket limit that developers should be aware of when the system uses the user space stack, and what are the best practices to manage large numbers of connections?

The Download is not Working in the background mode even if i entitled all the necessary permission for the application it only works when the app is connected to xcode due to xcode keep the session alive but if try after removing the connection from the xcode the app not able to keep the download after 45 sec what may be the reason my code var request = URLRequest(url: url) request.httpMethod = "GET" let bearerToken = SyncManager.accessToken request.setValue("Bearer \(bearerToken)", forHTTPHeaderField: "Authorization") let uniqueIdentifier = "\(self.vdmsId)_\(UUID().uuidString)" backgroundTaskID = UIApplication.shared.beginBackgroundTask { [weak self] in if let taskID = self?.backgroundTaskID { UIApplication.shared.endBackgroundTask(taskID) self?.backgroundTaskID = .invalid } } let CursessionConfig = URLSessionConfiguration.background(withIdentifier: uniqueIdentifier) CursessionConfig.isDiscretionary = false CursessionConfig.sessionSendsLaunchEvents = true CursessionConfig.shouldUseExtendedBackgroundIdleMode = true // Set timeout intervals CursessionConfig.timeoutIntervalForResource = 24 * 60 * 60 // 24 hours CursessionConfig.timeoutIntervalForRequest = 60 * 60 // 1 hour let Cursession = URLSession(configuration: CursessionConfig, delegate: self, delegateQueue: nil) self.CurInstanceSession = Cursession self.session = Cursession if SyncManager.activeSessions == nil { SyncManager.activeSessions = [URLSession]() } SyncManager.activeSessions?.append(Cursession) self.downloadCompletionHandler = completion let CurdownloadTask = Cursession.downloadTask(with: request) CurdownloadTask.resume() is there any solutions and i have entitled all the neccessary permisssions like background fetch, process and i also tries with the UIApplication.shared.beginBackgroundTask but after 45 sec it gets terminated all of the suden what may be the issue

Hi, We are working on an app that communicates over a UDP connection on the local network. In our testing, we have a Python UDP client running on the same network, which responds when we send a message to a broadcast IP (255.255.255.255). This setup works as expected on an iOS 15 device. However, when we test the same scenario on an iOS 18 device, the UDP communication doesn't seem to reach the Python UDP client. We've verified that the UDP client and the iOS device are on the same network, and the Python client is responding correctly. Has Apple introduced any restrictions or changes regarding UDP broadcast behavior in iOS 18? Is broadcasting to 255.255.255.255 still supported, or has this functionality been limited in recent iOS versions?

I am trying to connect an iPhone 16 (iOS 18.3) to a Wi-Fi device with the SSID "DIRECT-DR_6930_KP201128", but every time, without being able to enter the Wi-Fi password, the message "Unable to join the network 'DIRECT-DR_6930_KP201128'" is displayed. Below are the system logs from the connection failure. Could you please tell me the cause of the connection failure? By the way, an iPhone SE 2nd (iOS 18.2.1) can connect to the same Wi-Fi device without any issues. System Logs: ・Jan 31 19:18:14 900-iPhone-16-docomo Preferences(WiFiKit)[351] : {ASSOC-} association finished for DIRECT-DR_6930_KP201128 - success 0 ・Jan 31 19:18:14 900-iPhone-16-docomo runningboardd(RunningBoard)[33] : Assertion 33-351-4412 (target:[app<com.apple.Preferences(DE1AB487-615D-473C-A8D6-EAEF07337B18)>:351]) will be created as inactive as start-time-defining assertions exist ・Jan 31 19:18:14 900-iPhone-16-docomo Preferences(WiFiKit)[351] : association failure: (error Error Domain=com.apple.wifikit.error Code=12 "Unknown Error" UserInfo={NSDebugDescription=Unknown Error, NSUnderlyingError=0x303307660 {Error　Domain=com.apple.corewifi.error.wifid Code=-3938 "(null)"}}) ・Jan 31 19:18:14 900-iPhone-16-docomo Preferences(WiFiKit)[351] : dismissing credentials view controller for DIRECT-DR_6930_KP201128

Could anyone teach me how to ask iOS 18 to have a prompt during set-up process of a new APP if user accidentally turns off Local Network ?

On iOS 18.3, I noted that partition "HTTPCookiePropertyKey: StoragePartition" is not observed to be set for cookies returned from the wkwebview cookie store. Now on 18.4 beta 4 we are now seeing those same cookies are populated with a partition property. Is there documentation for this change? Is it intended to be suddenly populated in 18.4? Now that partition property is set, HTTPCookieStorage.shared.cookies(for: serverUri) doesn't seem to return the expected cookies correctly. For context, we are using the cookies extracted from wkwebview, setting them in HTTPCookieStorage.shared and using URLSession to make network calls outside the webivew. Works fine once I forcefully set partition on the cookie to nil. More details on what the cookie looks like here: https://feedbackassistant.apple.com/feedback/16906526 Hopefully this is on your radar?