Hey guys! It seems I just stumbled upon the exact same issue whilst developing a multiplatform (iOS and macOS) app that would use SSDP (and potentially other multicast-based protocols) to discover devices on the user's network. To ensure I'd follow Apple's guidelines as best as possible, I decided to go for the Network framework instead of another one (didn't see this post before I started). Unfortunately, this still seems to be an issue. Please see my playground code below for testing. I never get to see any response from clients, but Wireshark and TCPDump clearly show the outgoing and incoming packets. The code is ready to be dumped into Playground: import Foundation import Network final class SSDPBrowser {         private var queue = DispatchQueue.global(qos: .userInitiated)     private var listener: NWListener?     private var listeningPort: NWEndpoint.Port = 0     private var connection: NWConnection?     private var ssdpIP: NWEndpoint.Host = "239.255.255.250"     private var ssdpPort: NWEndpoint.Port = 1_900          public func connect() {         self.connection = NWConnection(host: self.ssdpIP, port: self.ssdpPort, using: .udp)         connection!.stateUpdateHandler = { (newState) in             switch (newState) {             case .preparing:                 print("Entered state: preparing")             case .ready:                 print("Entered state: ready")             case .setup:                 print("Entered state: setup")             case .cancelled:                 print("Entered state: cancelled")             case .waiting:                 print("Entered state: waiting")             case .failed:                 print("Entered state: failed")             default:                 print("Entered an unknown state")             }         }         connection!.viabilityUpdateHandler = { (isViable) in             if (isViable) {                 print("Connection is viable")             } else {                 print("Connection is not viable")             }         }         connection!.betterPathUpdateHandler = { (betterPathAvailable) in             if (betterPathAvailable) {                 print("A better path is availble")             } else {                 print("No better path is available")             }         }         connection!.start(queue: .global())     }     public func sendSSDPDiscoveryPacket() {         let message = "M-SEARCH * HTTP/1.1\r\n" +                     "MAN: \"ssdp:discover\"\r\n" +                     "HOST: \(self.ssdpIP):\(self.ssdpPort)\r\n" +                     "ST: \"ssdp:all\"\r\n" +                     "MX: 10\r\n\r\n"         let payload = message.data(using: .utf8)         self.connection!.send(content: payload, completion: .contentProcessed({ sendError in             if let error = sendError {                 print("Unable to process and send data: \(error)")             } else {                 print("SSDP discovery packet has been sent:\r---\r\(message)")                 self.connection!.receiveMessage { (data, context, isComplete, error) in                     if let unwrappedError = error {                         print("Error: NWError received in \(#function) - \(unwrappedError)")                         return                     }                     guard isComplete, let data = data else {                         print("Error: Received nil Data with context - \(String(describing: context))")                         return                     }                     print("Received message: " + String(decoding: data, as: UTF8.self))                 }             }         }))     } } let ssdpBrowser = SSDPBrowser() ssdpBrowser.connect() ssdpBrowser.sendSSDPDiscoveryPacket() As a workaround, I went ahead and tried to test another framework based on Bluesockets called SSDPClient (https://github.com/resourcepool/ssdp-client), but that didn't work either. It seems the receive fails for some unknown reason (error 9982). Not even the basic example they propose on Github seems to work under Xcode 13 anymore. Do you have any update for us if and how things evolved with Bug 9120983, or maybe any other hint on what I can do to overcome this? Many thanks for your support in advance, Nicolas

Having a similar issues here! I am currently using Home Assistant in version 2023.11.0 (latest) as my main smart home system and also connected a SkyConnect dongle to it in order to be able to operate ZigBee as well as Thread/Matter devices with it. I just purchased a Nanoleaf Essential Lightstrip that uses Matter and whenever I try connecting the lightstrip to Home Assistant using my iPhone 15 Pro Max running iOS 17.0.3 (latest) the Apple Home dialog pops up from within the Home Assistant app and allows me to select the Nanoleaf Lightstrip. Once I click to add it to home, I receive the message that a Thread Border Router is required. Also if I try adding the Lightstrip directly from within the Apple Home app, I get the same warning. In my case, Home Assistant is providing the Thread Border Router capability, since I don’t own a HomePod or Apple TV. To do that, Home Assistant uses the Open Threat Border Router that should play nicely with the SkyConnect stick mentioned above. I‘ve done a lot of debugging and the Threat Border Router is definitely announcing its services which I confirmed on my iPhone using an app called Flame, but also using the CLI tool dns-sd on my Mac. It seems to me, that iOS for some reason ignores the OTBR and thus doesn’t let us pair matter devices and I would need to purchase an HomePod or Apple TV to make it work, whicj would totally differ from Matters purposes. Any idea how this could be fixed?