Network handover method when vehicle-mounted LTE UE is handed over across EPCs

Abstract

The invention relates to a network handover method in cross-EPC switching. According to the network transfer method in switching vehicle LTE UE cross EPCs, when vehicle terminals are operated cross lines and cross administrations, the behaviors of the terminals are completely taken over by the EPC of a target road bureau; anchor points of data and signaling are handed over from the PGW (Packet Data Network Gateway) of a source EPC to the PGW of a target EPC without loss; in the cross-line switching handover process, the vehicle UE still keeps signaling and data connection with the source PGW through a Home Routed mode; when a target MME (Mobility Management Entity) sends a create session request to a target SGW (Serving Gateway), the target SGW also sends the create session request to the target PGW so as to create a session channel between the target SGW and the target PGW; and the SGW maintains two sets of uplink session contexts of the UE at the same time. According to the method provided by the invention, when switching the vehicle LTE UE cross EPCs, on the premise of ensuring uninterrupted data business, user data surfaces and signaling surfaces are handed over from the source PGW to the target PGW without loss; and seamless handover of the vehicle UE form the source PGW to the target PGW is realized.

Description

technical field [0001] The present invention relates to a network handover method during inter-EPC handover, in particular to a network handover method for vehicle-mounted LTE UE inter-EPC handover, which can achieve source PGW to target PGW under the condition that the data link is not interrupted lossless transfer. Background technique [0002] The current LTE 3GPP 23.401 protocol stipulates that when the UE is switched across EPCs in the connected state, if the continuity of the data plane and the signaling plane is maintained, the home routed method must be adopted. The signaling channel before the handover is the UE source eNB source MME source SGW source PGW, see figure 1 ;The data plane channel before handover is UE source eNB source SGW source PGW service system, see figure 2 . In order to maintain the continuity of the data plane during the handover in the connected state, the home routing method stipulates that the signaling plane after handover is from the UE ...

AI Technical Summary

Problems solved by technology

[0004] At present, the cross-EPC handover strategies of various equipment manufacturers are implemented according to the home routing method on LTE 3GPP. When applied on subways and railways, if the vehicle-mounted UE is switched from the source line EPC to the target line EPC, the data link will not be interrupted. In some cases, the lossless transfer from the source PGW to the target PGW cannot be achieved

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