Let's say you want to stop a server. https://developer.apple.com/forums/thread/75997 From searching apparently, there's an automatic cooldown. Don't know whether it's true or not. That thread mentions socket variables, that I don't believe can be used with the NW stuff. NWListener "cancel" doesn't seem to stop a server? Eitherways, doing that and trying to use .start and something like self.listener = try NWListener(using: self.cfg_nwParameters, on: self.port) self.listener?.start(queue: .main) this will trigger Address already in use if you "stopped" a server, because apparently you can't stop a server with NWListener. Because the socket isn't actually closing apparently.

Hello, I'm working with the Network framework in Swift and have encountered an issue when attempting to create multiple NWListener instances on the same port. I am specifically trying to set the allowLocalEndpointReuse property on the NWParameters used for both listeners, but it seems that even with this property set, the second listener fails to start. Here’s a simplified version of my implementation: import Foundation import Network class UDPServer { private var listener1: NWListener? private var listener2: NWListener? private let port: NWEndpoint.Port init(port: UInt16) { self.port = NWEndpoint.Port(rawValue: port) ?? NWEndpoint.Port(45000) startListeners() } private func startListeners() { let udpOptions = NWProtocolUDP.Options() let params = NWParameters(udp: udpOptions) params.allowLocalEndpointReuse = true // Create first listener do { listener1 = try NWListener(using: params, on: port) listener1?.start(queue: .global()) } catch { print("Failed to create Listener 1: \(error)") } // Create second listener do { listener2 = try NWListener(using: params, on: port) listener2?.start(queue: .global()) } catch { print("Failed to create Listener 2: \(error)") } } } // Usage example let udpServer = UDPServer(port: 45000) RunLoop.main.run() Observations: I expect both listeners to operate without issues since I set allowLocalEndpointReuse to true. However, when I attempt to start the second listener on the same port, it fails with an error. output nw_path_evaluator_evaluate NECP_CLIENT_ACTION_ADD error [48: Address already in use] nw_path_create_evaluator_for_listener nw_path_evaluator_evaluate failed nw_listener_start_on_queue [L2] nw_path_create_evaluator_for_listener failed Listener 1 ready on port 45000 Listener 2 failed: POSIXErrorCode(rawValue: 48): Address already in use Listener 2 cancelled Questions: Is there a limitation in the Network framework regarding multiple listeners on the same port even with allowLocalEndpointReuse? Should I be using separate NWParameters for each listener, or is it acceptable to reuse them? Even when trying to initialize NWParameters with NWProtocolUDP.Options, it doesn't seem to change anything. What steps should I take to modify these properties effectively? If I wanted to set the noDelay option for TCP, how would I do that? Even when initializing NWParameters with init(.tls: , .tcp:), it doesn't seem to have any effect. Any insights or recommendations would be greatly appreciated! Thank you!

Hello, I have a question about sending data in QUIC DATAGRAM. Regarding sending data in QUIC DATAGRAM, when I create a NWConnectionGroup and then use the send method of that group to send data in sequence, quite often I get an Optional(POSIXErrorCode(rawValue: 89): Operation canceled) error. A little Thread.sleep between sends improves the situation somewhat, but the above error still occurs. Also, since I want to send the frame data of the video in this communication process, adding a wait will drastically reduce performance and make the speed impractical. However, if send is executed continuously without adding weights, the above error will occur 80% of the time or more. Is it necessary to send while monitoring some status when sending? In communication using QUIC Stream, when connecting to the server with NWConnection and sending with its send method, the above error does not occur even if send is executed without wait, and data can be transferred with good performance. I am trying to use DATAGRAM communication to further increase throughput, but I am not having much success, and there is not much information on DATAGRAM communication. Thank you in advance for your help.

I am creating a VoIP application. The VoIP application needs to send and receive RTP packets at 20 ms intervals. The application calls sendto() of the Socket API at 20 ms intervals, but the iPhone buffers the send data inside iOS and then sends RTP packets in batches at 1 second intervals. (I captured the sned packets of iPhone with rvctl and confirmed this. please reffer "Sending at 1 second intervals.png" for detail) Similarly, other devices send RTP packets to the iPhone at 20 millisecond intervals, but the iPhone only receives them at 1 second intervals. (please reffer "Receiving at 1 second intervals.png" for detail) Why is this? If the cause of the delay is in the Wi-Fi protocol and the cause can be found from sysdiagnose, please tell me the search key for sysdiagnose that shows the cause of the delay and the meaning of the corresponding log. I uploaded sysdiagnose and result of lan capture to below. [sysdiagnose and lan capture] https://drive.google.com/file/d/149OPmePAF4hnZj6NeSnKc5NizfitPQDS/view?usp=sharing And, the start and end times, packet number in the lan capture of the call shown in the png example are below Start time; 13:57:22.349608/packet number; 948 End time; 13:57:37.482874/packet number; 2583

In the development environment, if I disable and then enable the Network Connection permission to my app in the Setting on my device, my app is denied the network connection permission permanently. The error message is The Internet connection appears to be offline. Please advise me what to do.

I need to connect to a JMS that publishes data that I need to collect. I am trying one solution: RabbitMQ with the JMS plugin. I succeeded to install RabbitMQ and send messages from one process to another. However, I need to consume a JMS that an external party publishes. Can anybody tell me how I should configure the Host, Port, Username, Password and Queue name for RabbitMQ/JMS so that I can consume (or subscribe to) that JMS? Or does anybody know another way to consume (or subscribe to) a JMS from Swift? I have no idea which of the provided Tags I should select. Thanks! Wouter

Hello. Wanted to ask about the right way, or the intended way to leverage NWConnectionGroup for a QUIC based streaming solution. The use case is, we are making a request from the client in order to play a movie, and we want to send as much video frames as possible (and as fast as possible) from the streaming server, which also uses the Network framework. Our understanding is, NWConnectionGroup will open a QUIC tunnel between both parties so we can multiplex different streams to the client and we are already doing that. We see a throughput of approx. 20-35MB/s (client device is an iPad and server is an M2 macbook pro running a server app) and we would like to understand if we can improve these results way more. For example: 1.- Is it a good practice to create a second tunnel (NWConnectionGroup), or is not needed here?. We tried that, but the second one is also coming with id 0 on the metadata object, just as the first group we instantiated, not sure why this is the case. 2.- We are using a pool of several NWConnection (initialized with the group object) already instantiated, that way we send a video buffer in chunks as a stream on each connection. We use one connection for a buffer and when we need to send another buffer we use a different NWConnection pulled from the pool. We maybe just want a confirmation/validation of what we are doing, or to see if we are missing something on our implementation... Thanks in advance.

Hello, I am planning to create an app that can transfer files to hardware devices via WiFi. With devices like GoPro, I believe the typical setup involves the GoPro creating a WiFi hotspot to which the iOS app connects, allowing file transfers. But this setup establishes a 1:1 connection between the app and the hardware. To support multiple hardware devices simultaneously, I am considering reversing this setup: the iOS device would create a personal hotspot, and the hardware devices would connect to it. However, I have concerns about this approach: Reliability: I have read that the personal hotspot feature on iOS devices can be unreliable, especially with non-Apple devices, which tend to disconnect frequently. Manual Setup: There is no API to programmatically create the personal hotspot, so users would have to enable it manually in the Settings. I can use isIdleTimerDisabled to prevent the iOS screen from going to sleep, which might help with disconnection issues. Aside from this, are there other things I can do to ensure a stable connection? Given my limited experience with hardware connections, I am uncertain if having the iOS device act as the WiFi access point is a good design. Any advice or alternative solutions would be greatly appreciated. Thank you in advance!

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

A few months ago, I remember reading some official documentation that was describing how to switch to a background upload when the app is about to be suspended. Unfortunately, I can't find that resource back, so it would be fantastic if someone would point it out to me. If I remember correctly, the procedure described was to start a regular upload task within some UIApplication.backgroundTask, and in any case the upload wasn't finished at the moment the system would call the suspension handler, the upload was "transitioned" into a a background one while preserving the current progress (I think because it was using the same URLSession or something, hence why I want to find back the documentation!) Note that I don't want to start a background upload from the beginning (this is what we do already!). I'm mostly looking for that piece of documentation to experiment if that scheme would improve our upload performance. Thanks!