FIELD: communication technologies.
SUBSTANCE: invention relates to the field of communication technologies, and more specifically to a method, device and communication system. The effect is achieved in that the communication method includes: receiving by the network element of the access and mobility control function in the first public land mobile network a registration request message from the terminal device; and upon determining that the first condition is met, sending the configured network segment selection assistance information of the first public land mobile network to the terminal device. The first condition includes one of the following: the registration request message is an initial registration request message, or the registration request message is sent after the terminal device transitions from the second public land mobile network to the first public land mobile network.
EFFECT: ensuring that the network device sends the updated configured network segment selection assistance information to the terminal device while conserving network resources.
65 cl, 20 dwg, 1 tbl
