A computing system providing normal security services and high security services, comprising: hardware resources, grouped into a plurality of resource security levels; a processor core, switching between different security states including a normal security state for providing the normal security services and a high security state for providing the high security services, and assigning an user access right to a request in accordance with the security state of the processor core and a protection level of the computing system, wherein the user access rights indicate the resource security levels available to the request, wherein the higher the protection level, the lower the security level of the resources that can be assessed, and wherein, for a particular protection level of the computing system, the user access right assigned in the high security state further allows the request to use hardware resources of a higher resource security level in comparison with the normal security state, and, for a particular security state of the processor core, the user access right assigned for a lower protection level covers the user access right assigned for a higher protection level; and an access right checker, determining whether the request has the authority to use the hardware resources in accordance with the assigned user access right and the resource security levels of required hardware resources of the request, wherein: when determining that the request has the authority to use the hardware resources, the access right checker allows the request to be executed; and when determining that the request does not have the authority to use the hardware resources, the access rights checker responds the request with an exception. hardware resources, grouped into a plurality of resource security levels; a processor core, switching between different security states including a normal security state for providing the normal security services and a high security state for providing the high security services, and assigning an user access right to a request in accordance with the security state of the processor core and a protection level of the computing system, wherein the user access rights indicate the resource security levels available to the request, wherein the higher the protection level, the lower the security level of the resources that can be assessed, and wherein, for a particular protection level of the computing system, the user access right assigned in the high security state further allows the request to use hardware resources of a higher resource security level in comparison with the normal security state, and, for a particular security state of the processor core, the user access right assigned for a lower protection level covers the user access right assigned for a higher protection level; and an access right checker, determining whether the request has the authority to use the hardware resources in accordance with the assigned user access right and the resource security levels of required hardware resources of the request, wherein: when determining that the request has the authority to use the hardware resources, the access right checker allows the request to be executed; and when determining that the request does not have the authority to use the hardware resources, the access rights checker responds the request with an exception. when determining that the request has the authority to use the hardware resources, the access right checker allows the request to be executed; and when determining that the request does not have the authority to use the hardware resources, the access rights checker responds the request with an exception.