Method and apparatus for detecting false base station

A method, comprising:

• receiving, by a communication apparatus, system information from a network device, wherein the system information comprises a first signature of the system information, a first timestamp, and a correspondence between a terminal identifier range and a selection range of a physical random access channel sequence, and the first timestamp identifies a time at which the network device generates the first signature;
• based on the communication apparatus determining that a difference between a local time of the communication apparatus and the first timestamp is greater than or equal to a first threshold and that a check on the first signature succeeds, selecting, by the communication apparatus, a physical random access channel sequence based on an identifier of the communication apparatus and the correspondence between the terminal identifier range and the selection range of the physical random access channel sequence;
• sending, by the communication apparatus, a message 1 to the network device based on the selected physical random access channel sequence;
• receiving, by the communication apparatus, a second signature from the network device;
• verifying, by the communication apparatus, whether a difference between a second timestamp and the first timestamp is less than a second threshold, wherein the second timestamp identifies a time at which the communication apparatus receives the second signature;
• and
• checking, by the communication apparatus, the second signature using the identifier of the communication apparatus and a current system time, wherein the identifier of the communication apparatus is determined based on a terminal identifier range corresponding to the identifier of the communication apparatus.

A communication apparatus, wherein the apparatus comprises:

• a transceiver, configured to send system information to a terminal device, wherein the system information comprises a first signature of the system information, a first timestamp, and a correspondence between a terminal identifier range and a selection range of a physical random access channel sequence, and the first timestamp identifies a time at which the network device generates the first signature;
• and receive a message 1 from the terminal device;
• and
• a processor, configured to determine a terminal identifier range corresponding to the terminal device based on an identifier of a physical random access channel sequence corresponding to the message 1 and the correspondence between the terminal identifier range and the selection range of the physical random access channel sequence;
• and sign an identifier of the terminal device and a current system time using a private key corresponding to the network device, to obtain a second signature, wherein the identifier of the terminal device is determined based on the terminal identifier range corresponding to the terminal device, wherein
• the transceiver is further configured to send the second signature to the terminal device.

A communication apparatus, comprising:

• at least one processor coupled to at least one memory storing instructions and configured to execute the instructions to cause the apparatus to:
• receive system information from a network device, wherein the system information comprises a first signature of the system information, a first timestamp, and a correspondence between a terminal identifier range and a selection range of a physical random access channel sequence, and the first timestamp identifies a time at which the network device generates the first signature;
• based on a determination that a difference between a local time and the first timestamp is greater than or equal to a first threshold and a check on the first signature being successful select a physical random access channel sequence based on an identifier of the apparatus and the correspondence between the terminal identifier range and the selection range of the physical random access channel sequence;
• and
• send a message 1 to the network device based on the selected physical random access channel sequence;
• receive a second signature from the network device;
• and
• verify whether a difference between a second timestamp and the first timestamp is less than a second threshold, wherein the second timestamp identifies a time at which the apparatus receives the second signature;
• and check the second signature using the identifier of the apparatus and a current system time, wherein the identifier of the apparatus is determined based on a terminal identifier range corresponding to the identifier of the apparatus.