BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
FIG. 1 is a simplified schematic block diagram of the architecture of a typical, high-capacity SIM card, both according to the prior art and according to the present invention;
FIG. 2 shows the structure of a single partition and the storage area of the partition's attributes, according to a preferred embodiment of the present invention;
FIG. 3 shows a high-level logical view of an implementation of a storage control method, according to a preferred embodiment of the present invention;
FIG. 4 shows a high-level logical view of the control of access to data, determined by which access mode is active, by a single usage profile in the implementation of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention relates to systems and methods for an MNO to dynamically control the usage of memory within a high-capacity SIM card. The principles and operation for an MNO to dynamically control the usage of memory within a high-capacity SIM card, according to the present invention, may be better understood with reference to the accompanying description and the drawings.
Referring now to the drawings, FIG. 1 is a simplified block diagram of the architecture of a typical high-capacity SIM card, both according to the prior art and according to the present invention. A high-capacity SIM card 2 is shown having a SIM controller 4 responsible for legacy SIM functionalities. High-capacity SIM card 2 communicates with the host mobile phone (not shown) that SIM card 2 resides in using a standard SIM ISO 7816 interface 6. A flash-memory storage 8 provides high-capacity SIM card 2 with mass storage capabilities. Flash-memory storage 8 is controlled by a flash controller 10. Via flash controller 10, flash-memory storage 8 appears as a sector-based storage device (like a typical hard disk) to an application (not shown), and can be accessed either by an external application (via a memory interface 12), or internally (by SIM controller 4).
Memory interface 12 enables high-speed access to flash-memory storage 8 compared to the relatively low speed of ISO 7816 interface 6. Memory interface 12 is typically an MMC™ or SD™ interface, for example. Communication channel 14 is an internal interface that enables SIM controller 4 to access flash-memory storage 8. Communication channel 14 also provides the ability to supervise the data written to flash-memory storage 8 via memory interface 12.
Flash-memory storage 8 is shown divided into partitions 16. Each partition 16 appears as a separate logical device to an application or operating system running on the mobile phone. As depicted in FIG. 1, partitions 16 may be of different sizes. The number of partitions and the size of each partition are determined during a device-formatting operation which is performed according to MNO specifications. An MNO may also specify that preloaded content be placed on a partition. It is noted that a memory that is not partitioned at all is considered to have a single partition. To clarify the differentiation with the prior art, the present invention is an innovative way for an MNO to control a user's usage of the prior-art SIM card of FIG. 1.
FIG. 2 shows the structure of a single partition and the storage area of the partition's attributes, according to a preferred embodiment of the present invention. A single partition 20 is shown having a file allocation table (FAT) 22 that specifies the mapping between the partition's logical-sector addresses and physical storage-device addresses. A data region 24 is used to store data, with a small portion of data region 24 reserved for partition attributes 26 of partition 20. Partition attributes section 26 includes: an RD field 28, for storing a read attribute that specifies the read authorizations for partition 20; a WR field 30, for storing a write attribute that sets the write authorizations for partition 20; an EXC field 32, for storing an execution attribute that designates the application-execution authorizations for partition 20; a T field 34, for storing a timing attribute that contains timing information (e.g. partition 20 can be set to become automatically enabled or disabled at a certain time and date); and a P field 36, for storing a protection attribute that contains security-related information (e.g. whether partition 20 is encrypted and with what encryption scheme). Spare attribute fields 38 are available for adding part of an “off-the-shelf” product (e.g. application-specific data-tags for determining access rights) or may be used to store MNO-specific attributes, for example.
Partition attributes section 26 is controlled by an MNO. The MNO designates the default settings for the attributes for the high-capacity SIM card manufacturer. The MNO can later change the settings for the attributes for partition 20 (and each additional partition) either by connecting the associated high-capacity SIM card to a settings-management system (e.g. a personal computer) via an adaptor, and running a high-capacity SIM configuration application. Alternatively, the MNO can change the settings for the attributes via the mobile network when the high-capacity SIM card is installed in the subscriber's mobile phone. The latter approach takes advantage of communication channel 14 between SIM controller 4 and flash controller 10 (shown in FIG. 1).
FIG. 3 shows a high-level logical view of an implementation of a storage control method, according to a preferred embodiment of the present invention. A high-capacity SIM 40 containing a memory manager 42 is responsible for all memory-related activities. Memory manager 42 is an application executed by flash controller 10 of FIG. 1. Memory manager 42 is in communication with an MNO 44, via a wireless network connection 46 used by MNO 44 for changing partition usage profiles 48. Memory manager 42 controls access to a storage memory 50 according to partition usage profiles 48 for each partition. Storage memory 50 includes data region 24 of FIG. 2. Each usage profile 48 defines two or more operating modes of a given partition for determining the access rights of each partition 20. At any given time, only one operating mode is active. Partition usage profiles 48 are stored in a restricted-access region 51 of storage memory 50, and can be changed only by an authorized entity (e.g. MNO 44). The grey region between restricted-access region 51 and storage memory 50 is meant to indicate that access to restricted-access region 51 is restricted, and that access to storage memory 50 is regulated by memory manager 42. Each partition usage profile 48 in FIG. 3 corresponds to a partition attributes section 26 of one partition 20 as shown in FIG. 2. By changing the operating mode, access rights to the partitions are changed accordingly. The active operating mode is stored by setting RD field 28, WR field 30, and EXC field 32 (e.g. for single-bit fields, “read/write enabled” can be RD=1, WR=1, EXC=0; “read/write/execute disabled” can be RD=0, WR=0, EXC=0).
FIG. 4 shows a high-level logical view of the control of access to data, determined by which access mode is active, by a single usage profile (i.e. a given partition usage profile 48 of partition 20) in the implementation of FIG. 3. Within a given partition usage profile 48, an access mode 52 is enabled by MNO 44. Memory manager 42 allows or rejects various access requests 54 (e.g. read, write, and execute) received from applications 56 according to which access mode 54 that MNO 44 has enabled. For example, if MNO 44 has set usage profile 48 to “read-only” mode (as shown in FIG. 4), then applications 56 are allowed to read the associated partition 20 in storage memory 50, but are not allowed to write to partition 20 or execute partition 20. Based on access requests 54, various data channels 58 (e.g. unidirectional or bidirectional) become operative to applications 56.
It is noted that for any given partition usage profile 48, only one access mode 52 will be active. Thus, partition usage profile 48 is illustrated logically as a table of possible access modes 52 in FIG. 4, with only one of access modes 52 being selected by MNO 44 at any given time. For illustrative purposes, the read-only mode in FIG. 4 is shown as the active mode.
It should be noted that the host device, typically a mobile phone, is not involved in the process of controlling the partitions, thus, there is no need to install any software, or to run any application in the host device for this purpose. This makes the method of the present invention independent of the functional components that are not controlled by the MNO. It should also be noted that memory manager 42 can use part of the data transmitted to the host device to make the access-mode “control decision” (i.e. to modify the active access-mode setting based on such data) besides the pre-determined setting of the MNO. Since all data flowing into and out of storage memory 50 flows through the high-capacity SIM interface via communication channel 14, the control logic (i.e. of access modes 52 by partition usage profile 48 via memory manager 42), which is set by MNO 44, can make use of the data in the control decision.
For example, the high-capacity SIM interface can prevent the host device from storing data that contains specific data sequences. Such data sequences could be, for example, coded tags indicating proprietary or copyrighted material (i.e. media). Using digital rights-management (DRM) tools, MNO 44 optionally prevents illegal copies of such material from being downloaded to the host device by sending access-control data to memory manager 42, and provide the user with the option of acquiring the DRM usage rights. Such DRM tools, as well as a table of the restricted data-tag sequences, could be stored locally in restricted-access region 51 (e.g. in spare attribute fields 38 of partition attributes section 26 of FIG. 2). Such sequence tables could be updatable only by MNO 44, or could be managed directly by MNO 44. Management of such sequence tables by MNO 44 could include, for example, updating sequences in the tables from content providers that require such sequences being resident in a device subscribed to a service in which each item is checked for DRM authorization.
While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications, and other applications of the invention may be made.
Patent Application
20070259691
