Patent ID: 8908871

Claim:
A method for updating a home agent root key (HA-RK) in a mobile internet protocol (MIP) system that includes computer networking nodes, a computer networking node including computer hardware with non-transitory memory which store instructions when executed by the computer hardware implement functions, the method by the computer networking nodes comprising: generating, by an authentication authorization accounting (AAA) server computer networking node, a new HA-RK, and sending the new HA-RK to a network authentication server (NAS) computer networking node before expiry of an old HA-RK; wherein the generating, by the AAA server computer networking node, of the new HA-RK, and the sending of the new HA-RK to the NAS computer networking node before the expiry of the old HA-RK further comprises: determining whether a remaining lifetime of the old HA-RK is less than or equal to a lifecycle of a master session key (MSK) generated for a mobile station (MS) computer networking node; generating, by the AAA server computer networking node, the new HA-RK and sending the new HA-RK to the NAS computer networking node corresponding to the MS computer networking node through a message of an extensible authentication protocol (EAP) process upon a determination by the AAA server computer networking node or an AAA agent to the AAA server computer networking node that the remaining lifetime of the old HA-RK is less than or equal to the lifecycle of the MSK; wherein a lifecycle of each of the new HA-RK and the old HA-RK is greater than the lifecycle of the MSK; and wherein upon a determination that the old HA-RK is generated by a visited AAA (V-AAA) server computer networking node and the MSK is generated by a home AAA (HAAA) server computer networking node, a visited AAA (V-AAA) agent to the V-AAA server computer networking node records the lifecycle of the MSK in the EAP process, obtains the remaining lifetime of the old HA-RK from the V-AAA server computer networking node, and determines whether the remaining lifetime of the old HA-RK is less than or equal to the lifecycle of the MSK; or the V-AAA agent records the lifecycle of the MSK in the EAP process and transfers information about the lifecycle of the MSK to the V-AAA server computer networking node, and the V-AAA server computer networking node determines whether the remaining lifetime of the old HA-RK is less than or equal to the lifecycle of the MSK.