Hello 👋 I need to implement a logic for searching for devices with our own service type using Bonjour. Using the NWBrowser, I can receive a list of all devices and connect to them. I need to utilize a WebSocket connection. By the property endpoint of NWBrowser.Result objects I can create NWConnection. Below is my implementation which works fine on iOS 17: let params = NWParameters.tcp let webSocketOptions = NWProtocolWebSocket.Options() params.defaultProtocolStack.applicationProtocols.insert(webSocketOptions, at: 0) // The `endpoint` is from `browseResultsChangedHandler` of NWBrowser let connection = NWConnection(to: endpoint, using: params) However, it doesn't work on iOS 15 and 16 because of the crash: 2024-06-01 16:07:18.136068+0300 MyApp[591:16845549] [] nw_endpoint_get_url called with null endpoint 2024-06-01 16:07:18.136932+0300 MyApp[591:16845549] [] nw_endpoint_get_url called with null endpoint, dumping backtrace: [arm64] libnetcore-3100.102.1 0 Network 0x000000018530e174 __nw_create_backtrace_string + 188 1 Network 0x000000018538ba20 nw_endpoint_get_url + 852 2 Network 0x0000000185310020 nw_ws_create_client_request + 84 3 Network 0x0000000184f4b3cc __nw_ws_create_state_block_invoke + 416 4 Network 0x000000018504bc68 nw_protocol_options_access_handle + 92 5 Network 0x0000000184f41e98 nw_ws_create_state + 204 6 Network 0x0000000184f41aec __nw_protocol_copy_ws_definition_block_invoke_2 + 176 7 Network 0x0000000184f69188 nw_framer_protocol_connected + 348 8 Network 0x00000001854a6638 _ZL29nw_socket_handle_socket_eventP9nw_socket + 1560 9 libdispatch.dylib 0x0000000126b89d50 _dispatch_client_callout + 16 10 libdispatch.dylib 0x0000000126b8d208 _dispatch_continuation_pop + 756 11 libdispatch.dylib 0x0000000126ba48d4 _dispatch_source_invoke + 1676 12 libdispatch.dylib 0x0000000126b94398 _dispatch_workloop_invoke + 2428 13 libdispatch.dylib 0x0000000126ba0b74 _dispatch_workloop_worker_thread + 1716 14 libsystem_pthread.dylib 0x000000012371f814 _pthread_wqthread + 284 15 libsystem_pthread.dylib 0x000000012371e5d4 start_wqthread + 8 Also, there is the stack trace of bt-command in the debug console: * thread #20, queue = 'com.apple.network.connections', stop reason = EXC_BAD_ACCESS (code=1, address=0x0) * frame #0: 0x0000000123078c24 libsystem_platform.dylib`_platform_strlen + 4 frame #1: 0x00000001803c538c CoreFoundation`CFStringCreateWithCString + 40 frame #2: 0x0000000185310030 Network`nw_ws_create_client_request + 100 frame #3: 0x0000000184f4b3cc Network`__nw_ws_create_state_block_invoke + 416 frame #4: 0x000000018504bc68 Network`nw_protocol_options_access_handle + 92 frame #5: 0x0000000184f41e98 Network`nw_ws_create_state + 204 frame #6: 0x0000000184f41aec Network`__nw_protocol_copy_ws_definition_block_invoke_2 + 176 frame #7: 0x0000000184f69188 Network`nw_framer_protocol_connected + 348 frame #8: 0x00000001854a6638 Network`nw_socket_handle_socket_event(nw_socket*) + 1560 frame #9: 0x0000000126b89d50 libdispatch.dylib`_dispatch_client_callout + 16 frame #10: 0x0000000126b8d208 libdispatch.dylib`_dispatch_continuation_pop + 756 frame #11: 0x0000000126ba48d4 libdispatch.dylib`_dispatch_source_invoke + 1676 frame #12: 0x0000000126b94398 libdispatch.dylib`_dispatch_workloop_invoke + 2428 frame #13: 0x0000000126ba0b74 libdispatch.dylib`_dispatch_workloop_worker_thread + 1716 frame #14: 0x000000012371f814 libsystem_pthread.dylib`_pthread_wqthread + 284 I have found out a couple things: There are no crashes if I initialize the NWConnection object with using, for instance, the NWEndpoint.url(_:). initializer: let urlHost = URL(string: "ws://10.20.30.40:5060")! let endpoint = NWEndpoint.url(urlHost) let params = NWParameters.tcp let webSocketOptions = NWProtocolWebSocket.Options() params.defaultProtocolStack.applicationProtocols.insert(webSocketOptions, at: 0) let connection = NWConnection(to: endpoint, using: params) self.connection = connection But, in this case, I must extract IP-addresses 🙇‍♂️ Meanwhile, there is a topic such as Don’t Try to Get the Device’s IP Address.. I have tried to find anything that could help me move forward in this problem and run into some odd behaviour. There is a property skipHandshake of NWProtocolWebSocket.Options object. If I set the property value to true, there are no crashes as well as no connection to a device.

I have an app that utilizes the Network Extension ( Packet Tunnel Provider ), but also uses MDNS to find local devices for data transfer via Network Extensions. However, once connected over Peer to Peer using AWDL0 or NWConnections, it works as expected until a user shuts the screen down. It looks like there's a difference in behavior when the device is plugged in vs when it's on just battery alone. So we can be happily sending data over p2p ( awdl0 ) then a screen shuts off and it kills the connection. Is this expected behavior and if so is there documentation? Also, Network Extensions do not appear to be able to discover over P2P, they can only connect to endpoints directly. Is this expected behavior? My thoughts; If a user allows both the Network Extension Permission and Local Network Permissions that the Network Extension should be able to discover peers via p2p. The connections ( if not asleep ) should stay active while in use.

Hi, I observed some unexpected behavior and hope that someone can enlighten me as to what this is about: mDNSResponder prepends IP / network based default search domains that are checked before any other search domain. E.g. 0.1.168.192.in-addr.arpa. would be used for an interface with an address in the the 192.168.1.0/24 subnet. This is done for any configured non-link-local IP address. I tried to find any mention of an approach like this in RFCs but couldn't spot anything. Please note that this is indeed a search domain and different from reverse-DNS lookups. Example output of tcpdump for ping devtest: 10:02:13.850802 IP (tos 0x0, ttl 64, id 43461, offset 0, flags [none], proto UDP (17), length 92) 192.168.1.2.52319 > 192.168.1.1.53: 54890+ [1au] A? devtest.0.1.168.192.in-addr.arpa. (64) I was able to identify the code that adds those default IP subnet based search domains but failed to spot any indication as to what this is about: https://github.com/apple-oss-distributions/mDNSResponder/blob/d5029b5/mDNSMacOSX/mDNSMacOSX.c#L4171-L4211 Does anyone here have an ideas as to what this might be about?

Like the post at https://forums.developer.apple.com/forums/thread/118035, I'm hitting an issue where I'm receiving: boringssl_session_set_peer_verification_state_from_session(448) [C1.1.1.1:2][0x12b667210] Unable to extract cached certificates from the SSL_SESSION object In my app logs. I tried to pin the SSL version to TLS 1.2 per Quinn's advice in that post, and then started digging further enabling CFNETWORK_DIAGNOSTICS=3 to see what was exposed on the Console.log (since it didn't show up in the Xcode console) The related log lines: 0 debug boringssl 15:43:04.978874-0700 MeetingNotes boringssl_context_log_message(2206) [C5:2][0x11080a760] Reading SSL3_RT_HANDSHAKE 16 bytes 0 debug boringssl 15:43:04.979007-0700 MeetingNotes boringssl_context_log_message(2206) [C5:2][0x11080a760] Writing SSL3_RT_CHANGE_CIPHER_SPEC 1 bytes 0 debug boringssl 15:43:04.979141-0700 MeetingNotes boringssl_context_log_message(2206) [C5:2][0x11080a760] Writing SSL3_RT_HANDSHAKE 16 bytes 0 debug boringssl 15:43:04.979260-0700 MeetingNotes nw_protocol_boringssl_write_bytes(87) [C5:2][0x11080a760] write request: 51 0 debug boringssl 15:43:04.979387-0700 MeetingNotes nw_protocol_boringssl_write_bytes(158) [C5:2][0x11080a760] total bytes written: 51 921460 debug boringssl 15:43:09.937961-0700 MeetingNotes boringssl_context_log_message(2206) [C5:2][0x11080a760] Writing SSL3_RT_ALERT 2 bytes 0 error boringssl 15:43:04.979630-0700 MeetingNotes boringssl_session_set_peer_verification_state_from_session(448) [C5:2][0x11080a760] Unable to extract cached certificates from the SSL_SESSION object Have a number of references to SSL3_RT in the messages, and I was curious if that indicated that I was using TLS1.3, which apparently doesn't support private shared keys. The constraints that I used riffs on the sample code from the tic-tac-toe example project: private static func tlsOptions(passcode: String) -> NWProtocolTLS.Options { let tlsOptions = NWProtocolTLS.Options() let authenticationKey = SymmetricKey(data: passcode.data(using: .utf8)!) let authenticationCode = HMAC<SHA256>.authenticationCode( for: "MeetingNotes".data(using: .utf8)!, using: authenticationKey ) let authenticationDispatchData = authenticationCode.withUnsafeBytes { DispatchData(bytes: $0) } // Private Shared Key (https://datatracker.ietf.org/doc/html/rfc4279) is *not* supported in // TLS 1.3 [https://tools.ietf.org/html/rfc8446], so this pins the TLS options to use version 1.2: // @constant tls_protocol_version_TLSv12 TLS 1.2 [https://tools.ietf.org/html/rfc5246] sec_protocol_options_set_max_tls_protocol_version(tlsOptions.securityProtocolOptions, .TLSv12) sec_protocol_options_set_min_tls_protocol_version(tlsOptions.securityProtocolOptions, .TLSv12) sec_protocol_options_add_pre_shared_key( tlsOptions.securityProtocolOptions, authenticationDispatchData as __DispatchData, stringToDispatchData("MeetingNotes")! as __DispatchData ) /* RFC 5487 - PSK with SHA-256/384 and AES GCM */ // Forcing non-standard cipher suite value to UInt16 because for // whatever reason, it can get returned as UInt32 - such as in // GitHub actions CI. let ciphersuiteValue = UInt16(TLS_PSK_WITH_AES_128_GCM_SHA256) sec_protocol_options_append_tls_ciphersuite( tlsOptions.securityProtocolOptions, tls_ciphersuite_t(rawValue: ciphersuiteValue)! ) return tlsOptions } Is there something I'm missing in setting up the proper constraints to request TLS version 1.2 with a private shared key to be used? And beyond that, any suggestions for debugging or narrowing down what might be failing?

I am trying to download XCode apps from my Mac to my Apple Vision Pro for testing. I have tried following the instructions by going into Settings-&gt;General-&gt;Remote Devices on my Apple Vision Pro, but there my Mac does not show up as a possible connection. Per this page, I have made sure that both devices are connected to the same WiFi network, updated my Mac to Sonoma, and updated my AVP to the latest OS, and everything else that it asks for. I am able to mirror my display from my Mac but downloading apps from XCode does not work. I have also looked to enable Developer Mode by going to Settings -&gt; Privacy &amp; Security -&gt; Enable Developer Mode, but there is no option for enabling developer mode here. Per this forum, my best guess is that it is a Bonjour Protocol compatibility issue since both devices are on university wifi (WPA2), but I also tried connecting both over a hotspot which also did not work.

Since the Multipeer Connectivity framework no longer supports Bluetooth. (https://developer.apple.com/forums/thread/749346) Why does its official documentation still mention "In iOS, the framework uses infrastructure Wi-Fi networks, peer-to-peer Wi-Fi, and Bluetooth personal area networks for the underlying transport." ?(https://developer.apple.com/documentation/multipeerconnectivity) What is the purpose of using Bluetooth personal area networks for the underlying transport?

Hello, In this inquiry（https://developer.apple.com/forums/thread/747860）, I came across this conclusion. “Apple disabled TCP/IP networking over Bluetooth completely. Apple’s peer-to-peer networking APIs now run exclusively over Wi-Fi." I have three questions I would like to ask. The Multipeer Connectivity Framework supports Wi-Fi networks, peer-to-peer Wi-Fi, and Bluetooth personal area networks. Since the framework abstracts away the underlying protocols, we cannot specify which protocol to choose. Can this framework still establish a pure Bluetooth connection now? (Not just using Bluetooth for the discovery phase). Given that the framework supports Bluetooth protocols, why does it not require Bluetooth permissions but only local network permissions? Does the Bluetooth protocol supported by the framework have the capability to discover traditional Bluetooth devices and services that the Core Bluetooth framework can discover?

I am currently attempting to resolve the hostname of a device connected to the same Wi-Fi network as mine. However, I've been unable to find sufficient resources or documentation on utilising the NBNS (NetBIOS Name Service) protocol for this purpose. Can someone please provide guidance on how to achieve this?

I compiled the Bonjour source code myself both for Linux and windows. Then I succeed in publishing and detecting services for two Windows devices. But I can't use Bonjour between a windows device and a Linux device. So is this a limitation? If not, any tips on how to solve it?

Using the Bonjour service requires obtaining local network permissions, but the Bonjour service also scans nearby devices through Bluetooth. Why doesn't Bluetooth permission be required? https://developer.apple.com/library/archive/qa/qa1753/_index.html#apple_ref/doc/uid/DTS40011315/ Did I misunderstand? Is there an issue with the design of iOS here?

Local network permissions are required to use the Bonjour service, But Bonjour service can also detect nearby devices through Bluetooth scanning without Bluetooth permission. https://developer.apple.com/library/archive/qa/qa1753/_index.html#apple_ref/doc/uid/DTS40011315/ Did I misunderstand? Or is there an issue with Apple's design here?

unresolved external symbol _mdns_malloc@4 referenced in function _syslog dnssd \mDNSResponder-2200.80.16\mDNSWindows\DLL\dnssd_clientstub.obj unresolved external symbol _mdns_free@4 referenced in function _syslog dnssd \mDNSResponder-2200.80.16\mDNSWindows\DLL\dnssd_clientstub.obj

I'm attempting to create a service that: Listens on iOS device A using NWListener Broadcasts the NWService ( using NWListener(service:using:)) ) on Bonjour Allows a separate device, iOS device B, to receive information about that service via an NWBrowser Connect to that service using the information contained in NWBrowser.Result 's NWEndpoint I've been able to successfully do this using a SwiftNIO service, in the following environments: iOS device A and iOS device B are physical iOS devices on the same WiFi network. This works. iOS device A and iOS device B are iOS simulators on the same machine. This works. iOS device A is a physical device, and iOS device B is a simulator. iOS device A is not connected to a WiFi network, iOS device B is connected to a WiFi network. This works. However, when iOS device A and iOS device B are physical devices that are not connected to a WiFi network, I encounter the following behavior: The Bonjour service is correctly advertised, and iOS device A and iOS device B are able to observe the advertisement of the service. In both cases, iOS device A and iOS device B, while able to resolve an NWEndpoint for the Bonjour service, are not able to connect to each other, and the connection attempt hangs. My setup for the listener side of things looks roughly like: let opts: NWParameters = .tcp opts.includePeerToPeer = true opts.allowLocalEndpointReuse = true let service = NWListener.Service(name: "aux", type: BONJOUR_SERVICE_TYPE, domain: "") try bootstrap.withNWListener(NWListener(service: service, using: opts)).wait() // bootstrap is an artifact of using SwiftNIO Similarly, my setup on the discovery side of things looks like: let params: NWParameters = .tcp params.includePeerToPeer = true let browser = NWBrowser(for: .bonjour(type: BONJOUR_SERVICE_TYPE, domain: BONJOUR_SERVICE_DOMAIN), using: params) browser.browseResultsChangedHandler =  { (searchResults, changed) in // save the result to pass on its NWEndpoint later } and finally, where I have an NWEndpoint, I use SwiftNIO's NIOTSConnectionBootstrap.connect(endpoint:) to initialize a connection to my TCP service ( a web socket server ). The fact that I am able to get P2P networking (presumably over an awdl interface?) between the simulator and the iOS device suggests to me that I haven't done anything obviously wrong in my setup. Similarly, the fact that it works over the same WiFi network and that, in P2P, I am able to at least observe the Bonjour advertisement, strikes me that I'm somewhere in the right neighborhood of getting this to work. I've also ensured that my Info.plist for the app has a NSLocalNetworkUsageDescription and NSBonjourServices for the Bonjour service type I'm browsing for. I've even attempted to exercise the "Local Network Permission" dialog by using a hacky attempt that sends data to a local IP in order to trigger a permissions dialog, though the hack does not appear to actually force the dialog to appear. Is there some trick or other piece of knowledge regarding allowing the use of P2P w/ Network.framework and TCP connections to services?

Hi, I'm new to swift programming and right now writing an app for esp8266-controlled lamp device. My lamp is broadcasting it's own IP through bonjour. So all I want is to discover any lamps in my network (http.tcp) and to read name and value. Is there any example of such implementation? All I found so far is old or a lit bit complicated for such simple question. Thanks in advance!

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.

IMPORTANT The approach used by this code no longer works. See TN3179 Understanding local network privacy for a replacement. Currently there is no way to explicitly trigger the local network privacy alert (r. 69157424). However, you can bring it up implicitly by sending dummy traffic to a local network address. The code below shows one way to do this. It finds all IPv4 and IPv6 addresses associated with broadcast-capable network interfaces and sends a UDP datagram to each one. This should trigger the local network privacy alert, assuming the alert hasn’t already been displayed for your app. Oh, and if Objective-C is more your style, use this code instead. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@apple.com" import Foundation /// Does a best effort attempt to trigger the local network privacy alert. /// /// It works by sending a UDP datagram to the discard service (port 9) of every /// IP address associated with a broadcast-capable interface. This should /// trigger the local network privacy alert, assuming the alert hasn’t already /// been displayed for this app. /// /// This code takes a ‘best effort’. It handles errors by ignoring them. As /// such, there’s guarantee that it’ll actually trigger the alert. /// /// - note: iOS devices don’t actually run the discard service. I’m using it /// here because I need a port to send the UDP datagram to and port 9 is /// always going to be safe (either the discard service is running, in which /// case it will discard the datagram, or it’s not, in which case the TCP/IP /// stack will discard it). /// /// There should be a proper API for this (r. 69157424). /// /// For more background on this, see [Triggering the Local Network Privacy Alert](https://developer.apple.com/forums/thread/663768). func triggerLocalNetworkPrivacyAlert() { let sock4 = socket(AF_INET, SOCK_DGRAM, 0) guard sock4 >= 0 else { return } defer { close(sock4) } let sock6 = socket(AF_INET6, SOCK_DGRAM, 0) guard sock6 >= 0 else { return } defer { close(sock6) } let addresses = addressesOfDiscardServiceOnBroadcastCapableInterfaces() var message = [UInt8]("!".utf8) for address in addresses { address.withUnsafeBytes { buf in let sa = buf.baseAddress!.assumingMemoryBound(to: sockaddr.self) let saLen = socklen_t(buf.count) let sock = sa.pointee.sa_family == AF_INET ? sock4 : sock6 _ = sendto(sock, &message, message.count, MSG_DONTWAIT, sa, saLen) } } } /// Returns the addresses of the discard service (port 9) on every /// broadcast-capable interface. /// /// Each array entry is contains either a `sockaddr_in` or `sockaddr_in6`. private func addressesOfDiscardServiceOnBroadcastCapableInterfaces() -> [Data] { var addrList: UnsafeMutablePointer<ifaddrs>? = nil let err = getifaddrs(&addrList) guard err == 0, let start = addrList else { return [] } defer { freeifaddrs(start) } return sequence(first: start, next: { $0.pointee.ifa_next }) .compactMap { i -> Data? in guard (i.pointee.ifa_flags & UInt32(bitPattern: IFF_BROADCAST)) != 0, let sa = i.pointee.ifa_addr else { return nil } var result = Data(UnsafeRawBufferPointer(start: sa, count: Int(sa.pointee.sa_len))) switch CInt(sa.pointee.sa_family) { case AF_INET: result.withUnsafeMutableBytes { buf in let sin = buf.baseAddress!.assumingMemoryBound(to: sockaddr_in.self) sin.pointee.sin_port = UInt16(9).bigEndian } case AF_INET6: result.withUnsafeMutableBytes { buf in let sin6 = buf.baseAddress!.assumingMemoryBound(to: sockaddr_in6.self) sin6.pointee.sin6_port = UInt16(9).bigEndian } default: return nil } return result } }

Hi, I am facing a strange issue in my app with iOS14 there is a intermittent crash, i am using NetServiceBrowser for MDNS discovery not sure if that is causing the problem crash log has below information: Crashed: com.apple.main-thread 0 CoreFoundation 0x1a906c4c4 CFAssertMismatchedTypeID + 108 1 CoreFoundation 0x1a8f7db0c CFRunLoopSourceRemoveFromRunLoop + 298 2 CFNetwork 0x1a96255b0 CFNetServiceBrowserStopSearch + 460 3 CoreFoundation 0x1a8f81240 CFRUNLOOPISCALLINGOUTTOASOURCE0PERFORMFUNCTION + 24 4 CoreFoundation 0x1a8f81140 CFRunLoopDoSource0 + 204 5 CoreFoundation 0x1a8f80488 CFRunLoopDoSources0 + 256 6 CoreFoundation 0x1a8f7aa40 CFRunLoopRun + 776 7 CoreFoundation 0x1a8f7a200 CFRunLoopRunSpecific + 572 8 GraphicsServices 0x1bf075598 GSEventRunModal + 160 9 UIKitCore 0x1ab840004 -[UIApplication run] + 1052 10 UIKitCore 0x1ab8455d8 UIApplicationMain + 164