| 摘要 |
A sequence of transmissions is encrypted as a set of sub-sequences, each sub-sequence having a different session key. The transmitting device determines when each new session key will take effect, and transmits this scheduled new-key-start-time to the receiving device. In a preferred embodiment, the transmitting device also transmits a prepare-new-key command to the receiving device, to provide a sufficient lead-time for the receiving device to calculate the new session key. Each new key is created using a hash function of a counter index and a set of keys that are determined during an initial key exchange session between the transmitting device and the receiving device. The counter index is incremented at each scheduled new-key-start-time, producing the new session key. |
