Patent attributes
A novel and useful mechanism for providing security features to a wireless communications system that otherwise does not have such features. Security features including encryption and decryption of communications, secure key exchange, secure pairing, and secure re-pairing are provided. The invention is applicable to wireless communication systems such as IO-Link Wireless. The encryption/decryption mechanism uses AES-256 block cypher with counter mode to generate blocks of cypher bits used to encrypt and decrypt communications between the master and devices. Session keys are generated using a random salt and a counter value. The random salt is generated using a secure random number generator such as the CSPRNG algorithm. A master key (or device key) is also used in generating session keys. Session keys are not permanent and are used to encrypt/decrypt only a finite amount of data. Once exhausted, the session key is replaced by a new one and cypher bits are generated using the new session key. A synchronized key jump procedure ensures that the master and device switch to the new session key at the same time.
