| 摘要 |
A system configurable at least between powered and unpowered states is provided. The system comprises a human interface device for receiving a multi-character alphanumeric code, one or more processors, memory storing programs executed by the processors, and a private key associated with the system. The one or more programs comprise instructions for evaluating usage of the system against a usage threshold. When usage of the system is within the usage threshold, the one or more processors permit the system to be in the powered state. When usage of the system exceeds the usage threshold, the one or more processors force the system to the unpowered state. Responsive to a determination that a received multi-character alphanumeric code is valid, the usage threshold is adjusted by an amount specified by the received code. |
