Patent ID: 11936773
Assignee: PENTA SECURITY INC.
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 12:
13. The apparatus of claim 12, wherein the instructions, when executed by the at least one processor, further causes the at least one processor to:
check a withdrawal of subscription of the first subscriber terminal;
generate an updated master key;
encrypt an updated master key with the public key of the supplier terminal and provide the supplier terminal with an encrypted and updated master key encrypted with the public key of the supplier terminal and the data identifier to enable the supplier terminal to decrypt the encrypted and updated master key encrypted with the public key of the supplier terminal and derive the symmetric key based on the master key, the data identifier, and the key update count value; and
encrypt the updated master key with the public key of the second subscriber terminal and provide the second subscriber terminal with an encrypted and updated master key encrypted with the public key of the second subscriber terminal and the data identifier to enable the second subscriber terminal to decrypt the encrypted and updated master key encrypted with the public key of the second subscriber terminal and derive the symmetric key based on the master key, the data identifier, and the key update count value.