Patent ID: 11863977
Assignee: HUAWEI TECHNOLOGIES CO., LTD.
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 11:
12. A terminal device, wherein the terminal device comprises:
a transceiver circuit configured to receive third key update information from a first communications apparatus implementing a session management function; and
a processor configured to
generate a new control plane key based on a control plane key and the third key update information,
generate a second key based on the new control plane key,
cause the transceiver circuit to send fourth key update information to the first communications apparatus implementing the session management function, wherein the first communications apparatus implementing the session management function is configured to:
generate the new control plane key based on the control plane key and the fourth key update information,
generate the second key based on the new control plane key, and
send the second key to a second communications apparatus implementing a user plane network function, and

using the second key, perform security protection on data transmitted between the second communications apparatus implementing the user plane network function and the terminal device, wherein
the control plane key is derived from a permanent key.