WiFi network connection issues with smartphones and tablets.
Apple phone software, called iOS, and also Android software installed on all other phones was updated some time ago to change the way that the phones connected to a WiFi network.
The change was made to the unique identifier that all network devices send out when they connect to networks. This identifier is called a Media Access Control address, or MAC address, and permits networks to identify the devices that are connecting. The MAC address should be fixed for a device.
The secret behind lightning-fast WiFi logins
Some networks record the MAC address so that when the device connects to the network several times, each time the connection is fast. This is important when the phone user is connecting to a hotel WiFi or other public network where the user has to provide an access code to connect to the network.
The change with Apple iOS and Android was that the MAC address is changed to a random number each time that the device connects to a WiFi network. The manufacturers call this ‘randomized MAC’. The reason that the device manufacturers added randomized MAC was for security. It becomes much more difficult for a cyber criminal to hack into a device that connects to a WiFi network when the MAC address constantly changes.
The changing MAC address is no problem for a business network or a home network, the network connection will take a few milliseconds longer as a different IP address will be issued, those networks do not store the MAC address of the device.
Most public WiFi networks such as those in hotels or airports do store the device MAC address as part of the login procedure. This facilitates the connection of the device because after the first login, the device does not have to be logged in again as the network remembers the MAC address of the device.
People who connect their randomized MAC devices to public WiFi networks will have to repeat the login process each time that they connect to the public WiFi network. These devices are not remembered as the MAC address has changed. This constant repeated login is a source of frustration for frequent travelers. However there is a solution.
Solution for the MAC address problem
The Apple and Android phones have a configuration feature to disable randomized MAC. This information to do that can be found by googling “disable randomized MAC for iOS” or “disable randomized MAC for Android”. With randomized MAC disabled, the device owner can login to a public WiFi network and remain logged in for all subsequent connections.