| 摘要 |
In service access networks having different key hierarchies that provide broadcast service to a mobile terminal, when switching from a first service access network, from which the mobile terminal receives the data of the broadcast service in an encrypted manner by a first data content encryption key, to a second service access network, from which the mobile terminal receives the data of the same broadcast service in an encrypted manner by a second data content encryption key, the mobile terminal receives a key of the hierarchy of the second service access network which is encrypted by a user-specific key of the first service access network. |
