Patent ID: 11924915
Assignee: T-MOBILE USA, INC.
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method comprising:
sending, by a mobile device, a first message to a first mobility management entity (MME) or a first access and mobility function (AMF) node;
receiving, by the mobile device, from the first MME or the first AMF node, a second message that includes a first list of equivalent public land mobile networks (PLMNs), wherein the first list of equivalent PLMNs is associated with a home network;
storing, by the mobile device, in memory of the mobile device, one or more PLMN codes included in the first list of equivalent PLMNs;
sending, by the mobile device, a third message to a second MME or a second AMF node;
receiving, by the mobile device, from the second MME or the second AMF node, a fourth message that includes a second list of equivalent PLMNs, wherein the second list of equivalent PLMNs is associated with a roaming network; and
after receiving the fourth message including the second list of equivalent PLMNs, maintaining, by the mobile device, the one or more PLMN codes of the first list of equivalent PLMNs in the memory.