Patent ID: 8474049

Claim:
A verification method used in an information processing apparatus having a virtual machine that executes processing relating to playback of contents, wherein the information processing apparatus holds therein a verification value table storing a value that dynamically changes while the information processing apparatus is executing processing, the value being dynamically changed so that the value corresponds to a predetermined address at predetermined time points, the verification method comprising: a reading step of reading a verification program recorded on a recording medium together with the contents; an execution step in which the virtual machine executes the verification program; a requesting step in which the verification program designates, at each predetermined time point, the predetermined address used for verification to be performed at the predetermined time point, and requests the virtual machine to acquire a value held at the predetermined address; an acquiring step in which the virtual machine, in response to the request, acquires the value held at the predetermined address designated by the verification program from the verification value table; a providing step in which the virtual machine provides the verification program with the value acquired in the acquiring step; and a verification step in which the verification program verifies whether the value provided in the providing step is a valid value that is to be provided when an execution environment including the virtual machine is valid, and determines that the execution environment including the virtual machine is invalid when the value is invalid.