Fix Apple Macbook Air/Pro Wifi Roaming Wireless Problems

As it can be expected from Apple, there is no user interface to adjust or change the wifi roaming agressiveness.
This is VERY IMPORTANT if for example you use Macbooks in a very dense wifi environment. If you have a Macbook that’s dropping packets when roaming or having trouble roaming from AP to AP, then open a terminal and run the following.

sudo /System/Library/PrivateFrameworks/Apple80211.framework/Versions/A/Resources/airport prefs joinMode=Strongest

Of the options available, the “strongest” option tells the wifi drivers on the Macbook to connect to the AP with the strongest (and thus hopefully the closest) AP, when multiple APs are available to connect to. Apple has configured the default setting to keep you connected to the same AP as long as possible, even if a better one is available. This is great at home, but not in a corporate environment.

Here are the other options available:
JoinMode (String)
- Automatic
- Preferred
- Ranked
- Recent
- Strongest


airport – the Little Known Command Line Wireless Utility for Mac

mDNS / Bonjour Bible – List of Common Service Strings for various vendors

For anyone who has struggled finding mDNS (aka Bonjour) service strings for various services, hopefully this will help you!

_adisk._tcp.localTime Capsule BackupsApple ProprietaryLink
_afpovertcp._tcp.local.AppleTalk Filing Protocol (AFP)Apple ProprietaryLink
_airdroid._tcp.local.AirDroid App3rd Party Custom 
_airdrop._tcp.local.OSX AirDropApple ProprietaryLink
_airplay._tcp.local.Apple TVApple ProprietaryLink
_airport._tcp.local.AirPort Base StationApple ProprietaryLink
_amzn-wplay._tcp.local.Amazon DevicesAmazon ProprietaryLink
*._sub._apple-mobdev2._tcp.local.OSX Wi-Fi SyncApple Proprietary 
_apple-mobdev2._tcp.local.OSX Wi-Fi SyncApple Proprietary 
_apple-sasl._tcp.local.Apple Password ServerApple ProprietaryLink
_appletv-v2._tcpApple TV Home SharingApple ProprietaryLink
_atc._tcp.local.Apple Shared iTunes LibraryApple ProprietaryLink
_sketchmirror._tcp.local.Sketch App3rd Party Custom 
_bcbonjour._tcpSketch App3rd Party CustomLink
_companion-link._tcp.localAirplay 2? UndocumentedApple ProprietaryLink
_cloud._tcp.localCloud by Dapile3rd Party CustomLink
_daap._tcp.localDigital Audio Access Protocol (DAAP)Apple ProprietaryLink
_device-info._tcp.local.OSX Device InfoApple ProprietaryLink
_distcc._tcp.local.Distributed CompilerApple ProprietaryLink
_dpap._tcp.local.Digital Photo Access Protocol (DPAP)Apple ProprietaryLink
_eppc._tcp.local.Remote AppleEventsApple ProprietaryLink
_esdevice._tcp.local.ES File Share App3rd Party Custom 
_esfileshare._tcp.local.ES File Share App3rd Party Custom 
_ftp._tcp.local.File Transfer Protocol (FTP)File ProtocolLink
_googlecast._tcp.local.Google Cast (Chromecast)Google ProprietaryLink
_googlezone._tcp.local.Google Zone (Chromecast)Google ProprietaryLink
_hap._tcp.local.Apple HomeKit – HomeKit Accessory ProtocolApple ProprietaryLink
_homekit._tcp.local.Apple HomeKitApple ProprietaryLink
_home-sharing._tcp.local.iTunes Home SharingApple ProprietaryLink
_http._tcp.local.Hypertext Transfer Protocol (HTTP)File ProtocolLink
_hudson._tcp.local.Jenkins App3rd Party CustomLink
_ica-networking._tcp.local.Image Capture SharingApple ProprietaryLink
_ichat._tcp.localiChat Instant Messaging ProtocolApple ProprietaryLink
_print._sub._ipp._tcp.local.Printers (AirPrint)Universal / SharedLink
_cups._sub._ipps._tcp.local.PrintersUniversal / Shared 
_print._sub._ipps._tcp.local.PrintersUniversal / Shared 
_jenkins._tcp.local.Jenkins App3rd Party CustomLink
_KeynoteControl._tcp.local.OSX KeynoteApple ProprietaryLink
_keynotepair._tcp.local.OSX KeynoteApple ProprietaryLink
_mediaremotetv._tcp.local.Apple TV Media RemoteApple ProprietaryLink
NDI Discovery for video streaming discoveryUniversal / SharedLink
_nfs._tcp.local.Network File System (NFS)File ProtocolLink
_nvstream._tcp.local.NVIDIA Shield Game Streaming3rd Party CustomLink
_androidtvremote._tcp.local.Nvidia Shield / Android TV3rd Party ProprietaryLink
_omnistate._tcp.local.OmniGroup (OmniGraffle and other apps)3rd Party CustomLink
_pdl-datastream._tcp.localPDL Data Stream (Port 9100)Apple ProprietaryLink
_photoshopserver._tcp.local.Adobe Photoshop Nav3rd Party CustomLink
_printer._tcp.local.Printers – Line Printer Daemon (LPD/LPR)Universal / SharedLink
_raop._tcp.local.AirPlay – Remote Audio Output ProtocolApple ProprietaryLink
_readynas._tcp.local.Netgear ReadyNAS3rd Party CustomLink
_rfb._tcp.local.OSX Screen SharingApple ProprietaryLink
_physicalweb._tcp.local.Physical WebGoogle ProprietaryLink
_riousbprint._tcp.localRemote I/O USB Printer ProtocolApple ProprietaryLink
_rsp._tcp.local.Roku Server Protocol3rd Party CustomLink
_scanner._tcp.local.ScannersUniversal / SharedLink
_servermgr._tcp.localServer AdminApple ProprietaryLink
_sftp-ssh._tcp.local.Protocol – SFTPFile ProtocolLink
_sleep-proxy._udp.local.Wake-on-Network / Bonjour Sleep ProxyApple ProprietaryLink
_smb._tcp.local.Protocol – SMBFile ProtocolLink
_spotify-connect._tcp.local.Spotify Connect3rd Party CustomLink
_ssh._tcp.local.Protocol – SSHFile ProtocolLink
_teamviewer._tcp.local.TeamViewer3rd Party CustomLink
_telnet._tcp.local.Remote Login (TELNET)File ProtocolLink
_touch-able._tcp.local.Apple TV Remote App (iOS devices)Apple ProprietaryLink
_tunnel._tcp.local.TunnelFile ProtocolLink
_udisks-ssh._tcp.localUbuntu / Raspberry Pi Advertisement3rd Party CustomLink
_webdav._tcp.local.WebDAV File System (WEBDAV)File ProtocolLink
_webdav._tcp.local.WebDAV File System (WEBDAV)File ProtocolLink
_workstation._tcp.local.Workgroup ManagerApple ProprietaryLink
_xserveraid._tcp.local.Xserve RAIDApple ProprietaryLink

T-Mobile Wifi Calling – ER081 Firewall Port Summary

Open the following ports on your firewall:

  • TCP 5060-5061
  • UDP 4500 (aka IKE Traversal)  –  Note: This is the port the call data goes through

Additionally, you may need to let IKE Key Exchange traffic through.

  • UDP 500

Other errors:

REG99 – Go to and update your E911 address (even if you previously have)