Patent ID: 11943830
Assignee: HUAWEI TECHNOLOGIES CO., LTD.
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 11:
12. A communication method applied to a communication system comprising a control plane (CP) functional entity, a target radio access node (RAN), and a source RAN, the method comprising:
receiving, by the target RAN, a re-establishment request message from user equipment (UE);
sending, by the target RAN, a first message to the CP functional entity based on the re-establishment request message,
wherein the re-establishment request message comprises a second message authentication code (MAC) generation parameter and an MAC of the UE, the first message comprises the second MAC generation parameter and the MAC;
receiving, by the CP functional entity, the first message from the target RAN;
verifying, by the CP functional entity, the MAC based on the second MAC generation parameter comprised in the first message;
in response to successful verification of the MAC, sending, by the CP functional entity, the second message to the source RAN, wherein the second message is used to request the source RAN to send undelivered non-access stratum (NAS) packet data unit (PDU) of the UE to the CP functional entity; and
sending, by the source RAN, the undelivered NAS PDU of the UE stored on the source RAN to the CP functional entity.