Abstract: A method for using time from a trusted host device is disclosed. In one embodiment, an application on a memory device receives a request to perform a time-based operation from an entity authenticated by the memory device, wherein the entity is running on a host device. The application selects time from the host device instead of time from a time module on the memory device to perform the time-based operation and uses the time from the host device to perform the time-based operation. Other embodiments are disclosed, and each of the embodiments can be used alone or together in combination.

Abstract: A method for improving accuracy of a time estimate from a memory device is disclosed. In one embodiment, a memory device receives a time stamp and measures active time with respect to the received time stamp. The memory device determines accuracy of previously-measured active time and generates a time estimate using the measured active time, the accuracy of previously-measured active time, and the received time stamp. In another embodiment, measured active time is adjusted, with or without generating a time estimate. Other embodiments are disclosed, and each of the embodiments can be used alone or together in combination.

Abstract: A memory device for using time from a trusted host device is disclosed. In one embodiment, a memory device comprises a memory array and circuitry operative to provide a security system operative to authenticate an entity running on a host device, a time module that keeps track of time, and an application operative to perform a time-based operation, wherein the application is further operative to use time from the host device instead of time from the time module to perform the time-based operation. Other embodiments are disclosed, and each of the embodiments can be used alone or together in combination.

Abstract: A memory device with circuitry for improving accuracy of a time estimate used to authenticate an entity is disclosed. In one embodiment, a memory device receives a request to authenticate an entity. Before attempting to authenticate the entity, the memory device determines if a new time stamp is needed. If a new time stamp is needed, the memory device receives the new time stamp and then attempts to authenticate the entity using a time estimate based on the new time stamp. In another embodiment, the memory device comprises a plurality of different time stamp update policies (TUPs) that specify when a new time stamp is needed, and the determination of whether a new time stamp is needed is based on a TUP associated with the entity. Other embodiments are disclosed, and each of the embodiments can be used alone or together in combination.

Abstract: Host devices present both the host certificate and the pertinent certificate revocation lists to the memory device for authentication so that the memory device need not obtain the list on its own. Processing of the certificate revocation list and searching for the certificate identification may be performed concurrently by the memory device. The certificate revocation lists for authenticating host devices to memory devices may be stored in an unsecured area of the memory device for convenience of users.

Abstract: Continuous strings of certificates in a certificate chain received by a memory device sequentially in the same order that the strings are verified. Each string except for the last may be overwritten by the next one in the sequence.

Abstract: Host devices present both the host certificate and the pertinent certificate revocation lists to the memory device for authentication so that the memory device need not obtain the list on its own. Processing of the certificate revocation list and searching for the certificate identification may be performed concurrently by the memory device. The certificate revocation lists for authenticating host devices to memory devices may be stored in an unsecured area of the memory device for convenience of users.

Abstract: Continuous strings of certificates in a certificate chain received by a memory device sequentially in the same order that the strings are verified. Each string except for the last may be overwritten by the next one in the sequence.