There is a free wireless city wifi network near my home, which requires a mobile phone to receive a verification code for web authentication. Is this true?

CMCC is the wifi network hotspot of the mobile company. To connect to the network, web page authentication is required, and you need to enter your mobile phone number for authentication.

The ChinaNet network is a wifi network hotspot of the telecommunications company. To connect to this hotspot, you need to enter your mobile phone number and the telecommunications verification code to connect to the network. There will be a timer to show the connection time when you connect to the network.