| 摘要 |
The present invention reduces the burden of time and cost at the time of migrating to a safer system having a new cipher scheme. By letting a migration-stage device which has been subjected to a predetermined security-enhancement measure handle high-value content for only a given system-migration period, it is possible to avoid problems related to the time required for the migration, and smoothly migrate to a safer system. A device referred to herein as a device which has been subjected to a predetermined security-enhancement measure is, for example, a device in which only conventional cipher algorithms are supported but safety regarding more vulnerable areas other than the cipher scheme is ensured. |
