General: Forums subtopic: App & System Services > Networking TN3151 Choosing the right networking API Networking Overview document — Despite the fact that this is in the archive, this is still really useful. TLS for App Developers forums post Choosing a Network Debugging Tool documentation WWDC 2019 Session 712 Advances in Networking, Part 1 — This explains the concept of constrained networking, which is Apple’s preferred solution to questions like How do I check whether I’m on Wi-Fi? TN3135 Low-level networking on watchOS TN3179 Understanding local network privacy Adapt to changing network conditions tech talk Understanding Also-Ran Connections forums post Extra-ordinary Networking forums post Foundation networking: Forums tags: Foundation, CFNetwork URL Loading System documentation — NSURLSession, or URLSession in Swift, is the recommended API for HTTP[S] on Apple platforms. Network framework: Forums tag: Network Network framework documentation — Network framework is the recommended API for TCP, UDP, and QUIC on Apple platforms. Building a custom peer-to-peer protocol sample code (aka TicTacToe) Implementing netcat with Network Framework sample code (aka nwcat) Configuring a Wi-Fi accessory to join a network sample code Moving from Multipeer Connectivity to Network Framework forums post Network Extension (including Wi-Fi on iOS): See Network Extension Resources Wi-Fi Fundamentals TN3111 iOS Wi-Fi API overview Wi-Fi Aware framework documentation Wi-Fi on macOS: Forums tag: Core WLAN Core WLAN framework documentation Wi-Fi Fundamentals Secure networking: Forums tags: Security Apple Platform Security support document Preventing Insecure Network Connections documentation — This is all about App Transport Security (ATS). Available trusted root certificates for Apple operating systems support article Requirements for trusted certificates in iOS 13 and macOS 10.15 support article About upcoming limits on trusted certificates support article Apple’s Certificate Transparency policy support article What’s new for enterprise in iOS 18 support article — This discusses new key usage requirements. Technote 2232 HTTPS Server Trust Evaluation Technote 2326 Creating Certificates for TLS Testing QA1948 HTTPS and Test Servers Miscellaneous: More network-related forums tags: 5G, QUIC, Bonjour On FTP forums post Using the Multicast Networking Additional Capability forums post Investigating Network Latency Problems forums post WirelessInsights framework documentation iOS Network Signal Strength Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com"

IMPORTANT This FAQ has been replaced by TN3179 Understanding local network privacy. I’m leaving this post in place as a historical curiosity, but please consult the technote going forward. I regularly get asked questions about local network privacy. This is my attempt to collect together the answers for the benefit of all. Before you delve into the details, familiarise yourself with the basics by watching WWDC 2020 Session 10110 Support local network privacy in your app. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" Local Network Privacy FAQ With local network privacy, any app that wants to interact with devices on your network must ask for permission the first time that it attempts that access. Local network privacy is implemented on iOS, iPadOS, visionOS, and macOS. It’s not implemented on other platforms, most notably tvOS. IMPORTANT macOS 15 (currently in beta) introduced local network privacy support to the Mac. WWDC 2024 Session 10123 What’s new in privacy is the official announcement. This works much like it does on iOS, but there are some subtle differences. I’ll update this FAQ as I gain more experience with this change. Some common questions about local network privacy are: FAQ-1 What is a local network? FAQ-2 What operations require local network access? FAQ-3 What operations require the multicast entitlement? FAQ-4 Do I need the multicast entitlement? FAQ-5 I’ve been granted the multicast entitlement; how do I enable it? FAQ-6 Can App Clips access the local network? FAQ-7 How does local network privacy work with app extensions? FAQ-8 How do I explicitly trigger the local network privacy alert? FAQ-9 How do I tell whether I’ve been granted local network access? FAQ-10 How do I use the unsatisfied reason property? FAQ-11 Do I need a local network usage description property? FAQ-12 Can I test on the simulator? FAQ-13 Once my app has displayed the local network privacy alert, how can I reset its state so that it shows again? FAQ-14 How do I map my Multipeer Connectivity service type to an entry in the Bonjour services property? FAQ-15 My app presents the local network privacy alert unexpectedly. Is there a way to track down the cause? FAQ-16 On a small fraction of devices my app fails to present the local network privacy alert. What’s going on? FAQ-17 Why does local network privacy get confused when I install two variants of my app? FAQ-18 Can my app trigger the local network privacy alert when the device is on WWAN? Revision History 2024-10-31 Added a link to this FAQ’s replacement, TN3179 Understanding local network privacy. 2024-07-22 Added a callout explaining that local network privacy is now an issue on macOS. 2023-10-31 Fixed a bug in the top-level FAQ that mistakenly removed some recent changes. Added FAQ-18. 2023-10-19 Added a preamble to clarify that local network privacy is only relevant on specific platforms. 2023-09-14 Added FAQ-17. 2023-08-29 Added FAQ-16. 2023-03-13 Added connecting a UDP socket to FAQ-2. 2022-10-04 Added screen shots to FAQ-11. 2022-09-22 Fixed the pointer from FAQ-9 to FAQ-10. 2022-09-19 Updated FAQ-3 to cover iOS 16 changes. Made other minor editorial changes. 2020-11-12 Made a minor tweak to FAQ-9. 2020-10-17 Added FAQ-15. Added a second suggestion to FAQ-13. 2020-10-16 First posted.

Hi, I have a problem with my OpenVPN connection on my app with iOS 14.4. I perform my VPN configuration from an oven file, with a NETunnelProviderManager protocol, but when I perform the startVPNTunnel, it starts connecting and immediately disconnects. The error I see in the logs is the following: NESMVPNSession[Primary Tunnel:OpenVPN Client: -----(null)]: status changed to disconnected, last stop reason Plugin was disabled This happens to me when running my app on a physical iPad. Regards import NetworkExtension import OpenVPNAdapter class VPNConnection {          var connectionStatus = "Disconnected"              var myProviderManager: NETunnelProviderManager?          func manageConnectionChanges( manager:NETunnelProviderManager ) - String {         NSLog("Waiting for changes");         var status = "Disconnected"                  NotificationCenter.default.addObserver(forName: NSNotification.Name.NEVPNStatusDidChange, object: manager.connection, queue: OperationQueue.main, using: { notification in                          let baseText = "VPN Status is "                          switch manager.connection.status {             case .connected:                 status = "Connected"             case .connecting:                 status = "Connecting"             case .disconnected:                 status = "Disconnected"             case .disconnecting:                 status = "Disconnecting"             case .invalid:                 status = "Invalid"             case .reasserting:                 status = "Reasserting"             default:                 status = "Connected"             }                          self.connectionStatus = status                          NSLog(baseText+status)                      });         return status     }          func createProtocolConfiguration() - NETunnelProviderProtocol {         guard             let configurationFileURL = Bundle.main.url(forResource: "app-vpn", withExtension: "ovpn"),             let configurationFileContent = try? Data(contentsOf: configurationFileURL)         else {             fatalError()         }                  let tunnelProtocol = NETunnelProviderProtocol()         tunnelProtocol.serverAddress = ""         tunnelProtocol.providerBundleIdentifier = "com.app.ios"                  tunnelProtocol.providerConfiguration = ["ovpn": String(data: configurationFileContent, encoding: .utf8)! as Any]         tunnelProtocol.disconnectOnSleep = false                  return tunnelProtocol     }          func startConnection(completion:@escaping () - Void){         self.myProviderManager?.loadFromPreferences(completionHandler: { (error) in             guard error == nil else {                 // Handle an occurred error                 return             }                          do {                 try self.myProviderManager?.connection.startVPNTunnel()                 print("Tunnel started")             } catch {                 fatalError()             }         })     }          func loadProviderManager(completion:@escaping () - Void) {                           NETunnelProviderManager.loadAllFromPreferences { (managers, error) in             guard error == nil else {                 fatalError()                 return             }                          self.myProviderManager = managers?.first ?? NETunnelProviderManager()             self.manageConnectionChanges(manager: self.myProviderManager!)                          self.myProviderManager?.loadFromPreferences(completionHandler: { (error) in                 guard error == nil else {                     fatalError()                     return                 }                                  let tunnelProtocol = self.createProtocolConfiguration()                                  self.myProviderManager?.protocolConfiguration = tunnelProtocol                 self.myProviderManager?.localizedDescription = "OpenVPN Client Ubic"                                  self.myProviderManager?.isEnabled = true                                  self.myProviderManager?.isOnDemandEnabled = false                                  self.myProviderManager?.saveToPreferences(completionHandler: { (error) in                     if error != nil  {                         // Handle an occurred error                         fatalError()                     }                     self.startConnection {                         print("VPN loaded")                     }                 })             })         }     } }

The content filtering functionality works perfectly when I install the app directly on my mobile device from Xcode. However, when the app is distributed via TestFlight, the app does not prompt users to save configurations, which causes the configuration-saving process to fail. This app is meant for public use. As per my understanding from TN3134, content filter apps can be shipped for devices running iOS 16 and later. iOS app extension 9.0. supervised devices only iOS app extension 15.0. apps using Screen Time API iOS app extension 16.0. per app on managed devices

the app in ipad can not connect to tcp server in the same local network. libinfo check path: unsatisfied (Local network prohibited) reproduce steps: I update my ipad to iapd iOS/18.0 install the app make the app connect to tcp server in the windows which is in the same local network. the ipad trigger Local Network privacy alert I tap the allow button, I check the toggle of Local Network privacy is on as well I try to make the app connect to tcp server in the windows again, but can not connect to tcp server, the ipad system log: nw_path_libinfo_path_check [8F864AB4-C5E1-488D-B396-ECEC2F3FB77E IPv4#0423cc45:9520 tcp, legacy-socket, attribution: developer] libinfo check path: unsatisfied (Local network prohibited), interface: en0[802.11], ipv4, uses wifi 7. I try to make the app connect to tcp server in other windows. It connects successful. the ipad system log: nw_path_libinfo_path_check [C84DC25A-5A14-4080-ABAA-10ED24AE2D6D IPv4#7df62769:9520 tcp, legacy-socket, attribution: developer] libinfo check path: satisfied (Path is satisfied), interface: en0[802.11], ipv4, dns, uses wifi So please apple developer help investigate why the app can not connect to the tcp sever in the same local network, even though the toggle of local network permission is on in ipad os 18

Hello, I have a very basic quic client implementation. When you run this code with some basic quic server, you will see that we can't get a handle to stream identifier 0, but behavior is actually different when we use URLSession/URLRequest, and I can see that some information can be sent over the wire for stream identifier 0 with that implementation. You can find both code below I'm using to test this. I'd like to get more info about how I can use stream identifier 0 with NWMultiplexGroup, if I can't use it with NWMultiplexGroup, I need a workaround to use stream with id 0 and use multiple streams over the same connection. import Foundation import Network let dispatchQueue = DispatchQueue(label: "quicConnectionQueue") let incomingStreamQueue = DispatchQueue(label: "quicIncStreamsQueue") let outgoingStreamQueue = DispatchQueue(label: "quicOutStreamsQueue") let quicOptions = NWProtocolQUIC.Options() quicOptions.alpn = ["test"] sec_protocol_options_set_verify_block(quicOptions.securityProtocolOptions, { (sec_prot_metadata, sec_trust, complete_callback) in complete_callback(true) }, dispatchQueue) let parameters = NWParameters(quic: quicOptions); let multiplexGroup = NWMultiplexGroup(to: NWEndpoint.hostPort(host: "127.0.0.1", port: 5000)) let connectionGroup = NWConnectionGroup(with: multiplexGroup, using: parameters) connectionGroup.stateUpdateHandler = { newState in switch newState { case .ready: print("Connected using QUIC!") let _ = createNewStream(connGroup: connectionGroup, content: "First Stream") let _ = createNewStream(connGroup: connectionGroup, content: "Second Stream") break default: print("Default hit: newState: \(newState)") } } connectionGroup.newConnectionHandler = { newConnection in // Set state update handler on incoming stream newConnection.stateUpdateHandler = { newState in // Handle stream states } // Start the incoming stream newConnection.start(queue: incomingStreamQueue) } connectionGroup.start(queue: dispatchQueue) sleep(50) func createNewStream(connGroup: NWConnectionGroup, content: String) -> NWConnection? { let stream = NWConnection(from: connectionGroup) stream?.stateUpdateHandler = { streamState in switch streamState { case .ready: stream?.send(content: content.data(using: .ascii), completion: .contentProcessed({ error in print("Send completed! Error: \(String(describing: error))") })) print("Sent data!") printStreamId(stream: stream) break default: print("Default hit: streamState: \(streamState)") } } stream?.start(queue: outgoingStreamQueue) return stream } func printStreamId(stream: NWConnection?) { let streamMetadata = stream?.metadata(definition: NWProtocolQUIC.definition) as? NWProtocolQUIC.Metadata print("stream Identifier: \(String(describing: streamMetadata?.streamIdentifier))") } URLSession/URLRequest code: import Foundation var networkManager = NetworkManager() networkManager.testHTTP3Request() sleep(5) class NetworkManager: NSObject, URLSessionDataDelegate { private var session: URLSession! private var operationQueue = OperationQueue() func testHTTP3Request() { if self.session == nil { let config = URLSessionConfiguration.default config.requestCachePolicy = .reloadIgnoringLocalCacheData self.session = URLSession(configuration: config, delegate: self, delegateQueue: operationQueue) } let urlStr = "https://localhost:5000" let url = URL(string: urlStr)! var request = URLRequest(url: url, cachePolicy: .reloadIgnoringLocalCacheData, timeoutInterval: 60.0) request.assumesHTTP3Capable = true self.session.dataTask(with: request) { (data, response, error) in if let error = error as NSError? { print("task transport error \(error.domain) / \(error.code)") return } guard let data = data, let response = response as? HTTPURLResponse else { print("task response is invalid") return } guard 200 ..< 300 ~= response.statusCode else { print("task response status code is invalid; received \(response.statusCode), but expected 2xx") return } print("task finished with status \(response.statusCode), bytes \(data.count)") }.resume() } } extension NetworkManager { func urlSession(_ session: URLSession, task: URLSessionTask, didFinishCollecting metrics: URLSessionTaskMetrics) { let protocols = metrics.transactionMetrics.map { $0.networkProtocolName ?? "-" } print("protocols: \(protocols)") } func urlSession(_ session: URLSession, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) { if challenge.protectionSpace.serverTrust == nil { completionHandler(.useCredential, nil) } else { let trust: SecTrust = challenge.protectionSpace.serverTrust! let credential = URLCredential(trust: trust) completionHandler(.useCredential, credential) } } }

For our outdoor power supply company that builds public WiFi networks at camping sites, we want to implement the following features in our app: Scan surrounding WiFi networks When detecting specific public WiFi SSIDs, provide users with corresponding passwords Automatically connect to those WiFi networks Regarding the NEHotspotHelper API permission application, when I clicked on https://developer.apple.com/contact/request/network-extension, it redirected me to https://developer.apple.com/unauthorized/. I'm not sure where to properly apply for this permission now.

I am trying to browse an SSH Service from UI Test Target using NWBrowser let descriptor = NWBrowser.Descriptor.bonjour(type: "_superapp._tcp", domain: "local.") let browser = NWBrowser(for: descriptor, using: .tcp) browser.stateUpdateHandler = { newState in print("browser.stateUpdateHandler \(newState)") } I get failed(-65555: NoAuth) error nw_browser_fail_on_dns_error_locked [B1] DNSServiceBrowse failed: NoAuth(-65555) I have added _superapp._tcp in Bonjour Services for UI Test Target Info.plist. I have also added Local Network Permission in UI Test Target Info.plist. Everything works fine, when I call this Bonjour service from App Target. Doesn't work when I call this from UI Test Target.

We have developed a DNS filter extension that works for most applications, but it does not receive all DNS queries. In particular, if we have our extension installed and enabled, we see Safari browsing cause local DNS servers to be used instead of going through our extension. What is the logic for how DNS servers vs. extensions are chosen to resolve DNS queries?

I am trying to connect to localhost:8081 from simulator, but it is unable to connect with following logs: info 12:07:49.167248+0530 com.apple.WebKit.Networking nw_resolver_host_resolve_callback [C8.1] flags=0x40000003 ifindex=0 error=NoSuchRecord(-65554) hostname=localhost. addr=IN6ADDR_ANY ttl=60 info 12:07:49.167310+0530 com.apple.WebKit.Networking nw_resolver_host_resolve_callback [C8.1] flags=0x40000002 ifindex=0 error=NoSuchRecord(-65554) hostname=localhost. addr=INADDR_ANY ttl=108002 Macos 14.6.1 iOS simulator version 17.5 Som observations localhost:8081 does not load on simulator but 0.0.0.0:8081 loads fine, also 127.0.0.0:8081 loads fine on simulator. My laptop is a managed device with network filter Switching network sometimes fixes the issue. Restarting laptop sometimes fixes the issue. localhost:8081 opens find on laptop, but not on simulator. Contents of my laptop's /etc/hosts: ## # Host Database # # localhost is used to configure the loopback interface # when the system is booting. Do not change this entry. ## 127.0.0.1 localhost 255.255.255.255 broadcasthost ::1 localhost

Hi, I have a problem about "NSPOSIXErrorDomain Code=65 & iOS18 & Xcode 16". I used 'CocoaAsyncSocket', '~> 7.6.5'. It works fine on iOS 15.2， But it's worried on iOS 18.3. Before this, broadcasts can be obtained normally。 I had get socket Multicast Networking. Please help me .

I tried building some app logic around NetworkMonitor.isConnected in my watch app (I want to trigger an update when the user opens the app and isConnected == true, otherwise observe NetworkMonitor.isConnected until it changes to true), and I found out that on a real device, NetworkMonitor.isConnected is always false. This does not seem to be documented anywhere. Am I right in assuming NetworkMonitor is not to be trusted on the watch? watchOS version is 18. I found an old post where eskimo argues that NWPathMonitor is not useful on the watch (which is also not documented), is it the same for NetworkMonitor? https://forums.developer.apple.com/forums/thread/127080

Most apps perform ordinary network operations, like fetching an HTTP resource with URLSession and opening a TCP connection to a mail server with Network framework. These operations are not without their challenges, but they’re the well-trodden path. If your app performs ordinary networking, see TN3151 Choosing the right networking API for recommendations as to where to start. Some apps have extra-ordinary networking requirements. For example, apps that: Help the user configure a Wi-Fi accessory Require a connection to run over a specific interface Listen for incoming connections Building such an app is tricky because: Networking is hard in general. Apple devices support very dynamic networking, and your app has to work well in whatever environment it’s running in. Documentation for the APIs you need is tucked away in man pages and doc comments. In many cases you have to assemble these APIs in creative ways. If you’re developing an app with extra-ordinary networking requirements, this post is for you. Note If you have questions or comments about any of the topics discussed here, put them in a new thread here on DevForums. Make sure I see it by putting it in the App & System Services > Networking area. And feel free to add tags appropriate to the specific technology you’re using, like Foundation, CFNetwork, Network, or Network Extension. Links, Links, and More Links Each topic is covered in a separate post: The iOS Wi-Fi Lifecycle describes how iOS joins and leaves Wi-Fi networks. Understanding this is especially important if you’re building an app that works with a Wi-Fi accessory. Network Interface Concepts explains how Apple platforms manage network interfaces. If you’ve got this far, you definitely want to read this. Network Interface Techniques offers a high-level overview of some of the more common techniques you need when working with network interfaces. Network Interface APIs describes APIs and core techniques for working with network interfaces. It’s referenced by many other posts. Running an HTTP Request over WWAN explains why most apps should not force an HTTP request to run over WWAN, what they should do instead, and what to do if you really need that behaviour. If you’re building an iOS app with an embedded network server, see Showing Connection Information in an iOS Server for details on how to get the information to show to your user so they can connect to your server. Many folks run into trouble when they try to find the device’s IP address, or other seemingly simple things, like the name of the Wi-Fi interface. Don’t Try to Get the Device’s IP Address explains why these problems are hard, and offers alternative approaches that function correctly in all network environments. Similarly, folks also run into trouble when trying to get the host name. On Host Names explains why that’s more complex than you might think. If you’re working with broadcasts or multicasts, see Broadcasts and Multicasts, Hints and Tips. If you’re building an app that works with a Wi-Fi accessory, see Working with a Wi-Fi Accessory. If you’re trying to gather network interface statistics, see Network Interface Statistics. There are also some posts that are not part of this series but likely to be of interest if you’re working in this space: TN3179 Understanding local network privacy discusses the local network privacy feature. Calling BSD Sockets from Swift does what it says on the tin, that is, explains how to call BSD Sockets from Swift. When doing weird things with the network, you often find yourself having to use BSD Sockets, and that API is not easy to call from Swift. The code therein is primarily for the benefit of test projects, oh, and DevForums posts like these. TN3111 iOS Wi-Fi API overview is a critical resource if you’re doing Wi-Fi specific stuff on iOS. TLS For Accessory Developers tackles the tricky topic of how to communicate securely with a network-based accessory. A Peek Behind the NECP Curtain discusses NECP, a subsystem that control which programs have access to which network interfaces. Networking Resources has links to many other useful resources. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" Revision History 2025-07-31 Added a link to A Peek Behind the NECP Curtain. 2025-03-28 Added a link to On Host Names. 2025-01-16 Added a link to Broadcasts and Multicasts, Hints and Tips. Updated the local network privacy link to point to TN3179. Made other minor editorial changes. 2024-04-30 Added a link to Network Interface Statistics. 2023-09-14 Added a link to TLS For Accessory Developers. 2023-07-23 First posted.

Hi everyone, I'm currently experimenting with building a simple DNS filter using Apple's Packet Tunnel framework. Here's the flow I'm trying to implement: Create a TUN interface Set up a UDP socket Read packets via packetFlow.readPackets Parse the raw IP packet Forward the UDP payload through the socket Receive the response from the server Reconstruct the IP packet with the response Write it back to the TUN interface using packetFlow.writePackets Here’s an example of an intercepted IP packet (DNS request): 45 00 00 3c 15 c4 00 00 40 11 93 d1 c0 a8 00 64 08 08 08 08 ed 6e 00 35 00 28 e5 c9 7f da 01 00 00 01 00 00 00 00 00 00 04 74 69 6d 65 05 61 70 70 6c 65 03 63 6f 6d 00 00 01 00 01 And here’s the IP packet I tried writing back into the TUN interface (DNS response): 45 00 00 89 5e 37 40 00 40 11 0b 11 08 08 08 08 c0 a8 00 64 00 35 ed 6e 00 75 91 e8 7f da 81 80 00 01 00 04 00 00 00 00 04 74 69 6d 65 05 61 70 70 6c 65 03 63 6f 6d 00 00 01 00 01 c0 0c 00 05 00 01 00 00 0c fb 00 11 04 74 69 6d 65 01 67 07 61 61 70 6c 69 6d 67 c0 17 c0 2c 00 01 00 01 00 00 03 04 00 04 11 fd 74 fd c0 2c 00 01 00 01 00 00 03 04 00 04 11 fd 74 7d c0 2c 00 01 00 01 00 00 03 04 00 04 11 fd 54 fb Unfortunately, it seems the packet is not being written back correctly to the TUN interface. I'm not seeing any expected DNS response behavior on the device. Also, I noticed that after creating the TUN, the interface address shows up as 0.0.0.0:0 in Xcode. The system log includes this message when connecting the VPN: NWPath does not have valid interface: satisfied (Path is satisfied), interface: utun20[endc_sub6], ipv4, dns, expensive, uses cellular Does anyone know how to properly initialize the TUN so that the system recognizes it with a valid IP configuration? Or why my written-back packet might be getting ignored? Any help would be appreciated!

NEAppProxyProvider MacOS Sequoia 15 never called “handleNewFlow” although it works well in the macOS Ventura/ Sonoma

Hello, I'm running into an issue while developing an iOS app that requires local network access. I’m using the latest MacBook Air M4 with macOS sequoia 15.5 and Xcode 16.1. In the iOS Simulator, my app fails to discover devices connected to the same local network. I’ve already added the necessary key to the Info.plist: NSLocalNetworkUsageDescription This app needs access to local network devices. When I run the app on a real device and M2 Chip Macbook's simulators, it works fine for local network permission as expected. However, in the M4 Chip Macbook's Simulator: The app can’t find any devices on the local network Bonjour/mDNS seems not to be working as well I’ve tried the following without success: Restarting Simulator and Mac Resetting network settings in Simulator Confirming app permissions under System Settings > Privacy & Security Has anyone else encountered this issue with the new Xcode/macOS combo? Is local network access just broken in the Simulator for now, or is there a workaround? Thanks in advance!

This post is part of the Local Network Privacy FAQ. What operations require local network access? The general rule is that outgoing traffic to a local network address requires that the user grant your app local network access. Common scenarios include: Making an outgoing TCP connection — yes Listening for and accepting incoming TCP connections — no Sending a UDP unicast — yes Sending a UDP multicast — yes Sending a UDP broadcast — yes Connecting a UDP socket — yes Receiving an incoming UDP unicast — no Receiving an incoming UDP multicast — yes Receiving an incoming UDP broadcast — yes These TCP and UDP checks are done at the lowest levels of the system and thus apply to all networking APIs. This includes Network framework, BSD Sockets, NSStream, and NSURLSession, and any other protocols that you layer on top of those. IMPORTANT Receiving an incoming UDP multicast or broadcast does not currently require local network access but, because we hope to change that in a future update, our advice right now is that you write your code as if did (r. 69792887, 70017649). Resolving link-local DNS names (those ending with local, per RFC 6762) requires local network access. Again, this check applies to a wide variety of APIs including <dns_sd.h>, <net_db.h>, Network framework, NSStream, and NSURLSession. Finally, all Bonjour operations require local network access: Registering a service with Bonjour — yes Browsing for Bonjour services — yes Resolving a Bonjour service — yes Again, these checks apply to all APIs that use Bonjour, including <dns_sd.h>, Network framework, NSNetService, and Multipeer Connectivity. Note You must declare the Bonjour service types you use in your Info.plist. See FAQ-14 How do I map my Multipeer Connectivity service type to an entry in the Bonjour services property? for details. Bonjour-based services where you don’t see any details of the network do not require local network access. These include: AirPlay — no Printing via UIKit — no Back to the FAQ

Apology for repost. I needed to fix the tags for original thread. https://developer.apple.com/forums/thread/777159 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?

Hello! I'd like to ask about the best way of getting a list of DNS servers from the system (iOS & macOS). Why? I am using NEPacketTunnelProvider to implement a VPN app. When a device joins a network with a Captive Portal and the VPN is on, the VPN should redirect DNS queries to the DNS servers that were received from the network's DHCP server. So that my VPN is able to correctly reroute the traffic which is not blocked by the network's gateway and the Captive Portal landing page is served. When I don't do anything, the traffic goes to the tunnel and the tunnel's encrypted traffic is then dropped by the gateway serving the Captive Portal. When I temporarily turn off the VPN, opt out of all the traffic or pass the traffic to the system resolver, the traffic gets affected by other network settings (like DNSSettings) which leads to the same situation - the user not being able to authenticate with the Captive Portal. So far, I have tried multiple ways, including res_9_getservers but unsuccessfully. As a part of my investigation, I have found out that the /etc/resolv.conf file is not populated with DNS servers until the Captive Portal is acknowledged by the user which makes getaddrinfo unusable to achieve my goal. But I am not sure if that's a bug or intended behavior. Thank you for your help!

I use eapolcfg in Apple's open source eap8021x repository to connect to the enterprise network. 1.https://github.com/gfleury/eap8021x-debug https://opensource.apple.com/source/eap8021x/eap8021x-304.100.1/ Our enterprise network authentication is PEAP. So far, I have created a profile using the following commands and have done the access. ./eapolcfg createProfile --authType PEAP --SSID myssid --securityType WPA2 --userDefinedName MyProfile ./eapolcfg setPasswordItem --password mypassword --name myname --SSID myssid ./eapolcfg startAuthentication --interface en0 --SSID myssid After I performed this series of operations, I passed BOOL success = [self.interface associateToEnterpriseNetwork:network identity:nil username:username password:password error:&amp;error]; Connection will pop up the following pop-up window, sometimes associateToEnterpriseNetwork will fail. I don't know what went wrong, is it that I missed some steps through the eapolcfg [tool?] This function also reports the following error：Error Domain=com.apple.coreWLAN.EAPOL.error Code=1 "(null)" Please answer my questions. Thank you very much

Hi, I have a hardware device that asks as an ethernet server. I need to connect to it using a TCP socket over ethernet. Problem is, I cannot find an API or example code on how to go about this. I have tried to search through the available network interfaces using AF_LINK (link layer) family but only the wifi shows up (en0), even when the device is connected and the iPhone self-assigns an IP etc. Extra challenge is, I am using objective C because all of my other code is written that way. I'm happy to add a swift module where that is the only option. Can someone please point me in the right direction?