Patent ID: 11924915

Abstract:
Disclosed herein are techniques, devices, and systems for a mobile device to keep track of public land mobile networks (PLMNs) codes from a list(s) of equivalent PLMNs that the mobile device received at a time of performing a past registration procedure(s). For example, memory of the mobile device may store a PLMN code(s) from a list of equivalent PLMNs that the mobile device received from a mobility management entity (MME) or an access and mobility function (AMF) node. During a subsequent registration, the mobile device may send a message to another MME or another AMF node, and may receive a message, such as an ATTACH ACCEPT message or a REGISTRATION ACCEPT message, from the other MME or the other AMF node. In response to receiving the message, the mobile device can maintain the stored PLMN code(s) in the memory.