FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10; Rule 13)
TITLE
METHOD FOR ACCESSING EXTENDED EXTERNAL MEMORY ON SIM / USIM / RUM CARD
APPLICANT
Giesecke & Devrient India Pvt. Ltd.
NATIONALITY : INDIA
of DEVELOPMENT CENTRE INDIA
9/1A, PADALE PRIME, OPP SHARADA CENTRE
ERANDWANE, PUNE 411 004
MAHARASHTRA
INDIA
The following specification particularly describes the nature of the invention and the manner in which it is to be performed.

Method For Accessing Extended External Memory on SIM / USIM / RUIM Card
Field of the Invention
The invention relates to Cloud SIMs, i.e., cloud memory usage (cloud storage concept providing unlimited virtual memory).
Background of the Invention
Throughout this article, SIM in general refers to Subscriber Identity Module (SIM) / USIM / RUIM and similar smart cards with processing capabilities.
The most constrained resource of a SIM card is its on-chip memory for data storage. With the ever increasing demand of memory for the SIM based applications, there has been always a challenge for Mobile Network Operator's (MNO) and SIM Suppliers to fit different applications in limited available memory.
Based on the application needs, a suitable Chip with sufficient memory is selected and then deployed into the market. Unlike many other embedded systems, this miniature device (SIM) could not be upgraded with memory for future memory requirements. The only available choice for SIM suppliers is to replace SIM with higher memory SIM, which also has the same limitation for memory requirements of future applications.
Generally SIM cards can host applications that may require human interface (like keypad, display, audio alert, etc) which are actually not present on the SIM card itself. However, the SIM can request the access of few limited resources from the terminal in which the SIM card is hosted (see Fig 1) as specified in 3GPP TS 51.014.
The proposed method describes a novel way to extend SIM card memory dynamically from external reliable sources (terminal / network) based on the needs.

Techniques used before this invention:
Some techniques that exist before this invention use physical coupling of SIM with external extendable memory devices like SD card, etc.
Ref: US 2003/0020800 Al / Jan 24, 2003
TWO-IN-ONE CONNECTOR FOR BOTH SIM CARD OF MOBILE PHONE AND MEMORY CARD
Ref: WO 2009156405 (Al) / Dec 30, 2009
SYSTEM AND METHOD OF EXTENDING SMART CARD CAPABILITY VIA A COUPLING WITH A PORTABLE ELECTRONIC DEVICE
Ref: KR 200300S2000 (A) / Sep 10, 2003
METHODS AND DEVICES FOR DATA ACCESS IN COMBINED SIM AND MASS STORAGE CARDS
Ref: US 2010050241 (Al) / Feb 25, 2010
ACCESSING MEMORY DEVICE CONTENT USING A NETWORK
Ref: US 20090020602 (Al) / Jan 22, 2009
METHOD FOR ESTABLISHING A SECURE LOGICAL CONNECTION BETWEEN AN INTEGRATED CIRCUTT CARD AND A MEMORY CARD THROUGH A TERMINAL EQUIPMEISTT
These methods demand a change in existing hardware and thus are not feasible for large scale deployment without disturbing the existing mobile communication eco-system.
The need for a hovel technique (method for dynamically extending memory of SIM from external sources (terminal/network)) arose from the fact SIM card prices are falling by the year whereas advanced SIM cards having smart SIM software of near 1 Gb capacity come with a high per unit price tag.

There are memory hungry applications. The existing constraint is reduced resource of on-chip memory of a SIM card for data storage. SIM based applications require increased memory. It is difficult to fit different applications in limited memory since a chip on a SIM has fixed memory sufficient for the application needs, but it cannot be upgraded for future memory requirements. Replacing with a higher memory SIM suffers from the same limitation in that memory falls short of future applications' memory requirement.
Further, SIM cards lack resources like display, keyboard, audio alert, eta and rely upon mobile devices for said resources (virtual capability) or can request access of limited resources from the terminal in which the SIM card is hosted (3GPP which defines sharing of hardware resources - "memory" sharing from mobile to SIM cards on request).
The prior art necessitates physical coupling of SIM with external SD card device. The prior art also demand a change in the existing hardware.
Summary of the Invention
According to the "method" of the present invention, SIM application can opt for memory storage location based on type of use. Appropriate memory storage location that can be opted for by the SIM include: (1) Mobile memory [for trivial and frequently accessed data that is required for the SIM application and is required only for the current session, e.g. Cell broadcast data]; (2) External SD card memory [for large and frequently accessed data, e.g. multi-language strings; (3) Terminal's memory pool (2) Terminal's OR memory (3) MNO's hosted server -[via Terminal] (4) Internet's public domain [via Terminal] data servers [for large and less frequently accessed data meant for sharing among user group].
The inventive solution involves dynamically extending memory of SIM from external sources (terminal/network) so that on-chip low memory of the SIM card can be optimally utilized for confidential data, e.g. keys, certificates, execution code, eta

Brief Description of the Accompanying Drawings
Objects and advantages will become apparent to those skilled in the art upon reading this description in conjunction with the accompanying drawings, in which:
Figure 1 shows SIM request generic resource from terminal;
Figure 2 shows SIM request memory resource anywhere within the eco-system;
Figure 3 shows File System on SIM;
Figure 4 shows SIM request memory resource anywhere within the eco-system;
Figure 5 shows typical example in roaming application; and
Figure 6 shows the handling of external (or cloud) files is new for the proposed new behavior.
DETAILED DESCRIPTION
Theory of operation of the method:
The proposed method uses resources in the existing mobile communication ecosystem and hence would be easier to penetrate into large scale deployments.
In the existing mobile communication eco-system, the memory is available at different level with different accessible scope, i.e., in Terminal, external memory devices (e.g. SD cards), Servers at Network operator, public hosted servers over internet (see Fig. 2).
Based on the type of use, the appropriate memory storage location can be opted by the SIM application.
1. The SIM application may request the Terminal to allocate memory from Terminal's memory pool, if the data is

a. required to persist only for current session (power-on to power-off),
b. too frequently accessed by the SIM application
The terminal creates a file in its file system and provides the 'handle' to the SIM.
2. The SIM application may request the Terminal to allocate memory in
Terminal OR in any of the Terminal's attached external devices like SD card,
if the data is
a. Large
b. required to persist across sessions
c. too frequently accessed by the SIM application
The terminal creates a file in its file system and provides the 'handle' to the SIM.
3. The SIM application may request the network operator's hosted server (via
Terminal) to allocate memory, if the data is
a. required to persist across sessions,
b. very much associated with network operator's service,
c. very large
d. less frequently accessed by the SIM application
The network operator's hosted server will then create a file in its file system and provide the 'handle' to the SIM.

4. The SIM application may send request over internet (via Terminal) to allocate memory in one of the public domains, if the data is
a. required to be shared with other users over internet
b. If the user has different accounts / network and is using a third party
application (like social networking site, etc),
The public domain server will then create a file in its file system and provide the 'handle' to the SIM.
Handling of files by SIM (existing behavior)
The communication between Terminal and SIM during file selection is described in brief below:

DESCRIPTION TERMINAL SIM
Terminal tries to select non-existing file on SIM AO A4 00 00 02 6F 39→
SIM responds Error condition ←5xxx
Terminal abort any further action on non- exist file
Terminal tries to select existing file on SIM Select File
AO A4 00 00 02 6F 3A→
SIM responds Success ←e9Fxx.
Terminal proceeds to further action on exist file
Handling of External files by SIM (proposed behavior)
The proposed communication between Terminal and SIM during file selection is described in brief below:
Existing behavior is supported as is:

Terminal tries to select norv existing file on SIM AO A4 DO 00 02 6F 39→
SIM responds Error condition ←6xxx
Terminal abort any further action on non- exist file
Terminal tries to select existing file on SIM Select File
AO A4 00 00 02 6F 3A→
SIM responds Success ←9Fxx
Terminal proceeds to further action on exist file
Proposed new behavior for external files is as below:

DESCRIPTION TERMINAL SIM

Terminal tries to select Select File
file on SIM A0 A4 00 00 02 6F 3B→
SIM identifies that this
file is "remotely located"
SIM enters to master mode ←91 xx
Terminal awaits till SIM gets
back to slave mode
Terminal serves the request A0 12 00 00 XX
from slave
SIM mentions further action. ←DD
The path where the file is
Located
Terminal process the
Information and access the
File.
Terminal provides the AO 14 00 00 YY
Information back to SIM
SIM responds Success for ←9Fxx
original file select from
Terminal
Cloud Storage Advantages :
• No need of additional hardware

• Resource balancing
• High scalability
• Pay as you grow (depending upon data usage)
•. Large virtual memory availability on low cost cards
• Increased SIM card life
• Cloud storage for SIM ca be hosted in leased servers or through channel
partners • Data sharing on usage fee basis • Recurring revenues from Cioud SIMs
Advantages of the method
The proposed method uses resources in the existing mobile communication ecosystem and hence would be easier to penetrate into large scale deployments.
Variety of SIM applications with large memory requirements can be deployed without constraints of chip memory.
All the limited, valuable & 'secure' on-chip memory of SIM can be used for executables, confidential data like secure keys, digital certificates etc - making it possible to load many applications on a given conventional SIM. The trivial information like scratch pad, temporary large buffers, language dependant info could be stored on distributed systems across the mobile network eco-system.
The application memory needs can be revised / reclaimed even after deployment.
Business advantage of holding the customer / market base
In traditional approach of replacing the SIM with new memory requirements does not guarantee hold on market as the same SIM vendor may not get the order from MNO.
Generally, the files are stored in SIM card's internal memory space with their references in its File Allocation Table {viz., FAT).

At the time of file creation, the "Cloud Files" are indicated as special files with relevant references in the FCP template in a predefined TLV structure.
For such files, the File Allocation Table is marked up accordingly. The file is then visible in logical file system for any accessing applications. Nevertheless, this Cloud File does not have the body in the local file system.
The above representation of FAT is only for illustrative purpose. The attributes required for FAT can be specific to implementation; the emphasis here is on the attribute that links the logical file in SIM file system to a physical file in a remote file system.
The remotely located files will have the same access rules as applied to normal files on the SIM card i.e., read, write, update access conditions based on PIN, etc mechanisms.
The proposed invention is better explained with following illustrative examples:
Example 1: SIM application accessing cloud files on ftp server
Please note, the example is only to illustrate typical use case and has nothing relevant to current invention. The principles of effective roaming application may be, much different than listed here.
Assuming a mobile network operator wishes to have a list of preferred mobile network partners in case one of his subscribers travels out of home network. This list can be exhaustive (occupy more space) and is more often dynamic in nature due to changing business interests of the operator. So, instead of keeping a file on SIM card with fixed size and. content, the operator may choose to create the file as "Cloud File".
Storing the list of partners in the Cloud File provides many benefits, following are listed few:

1. Subscribers who do not wish to use this feature, need not reserve space on valuable SIM space
2. The list can grow anytime as it is maintained in regular file on ftp or other relevant space that is easily resizable to any limit unlike restrictions on SIM space.
3. The data is accessed only when it is needed
When the subscriber moves out of home-network, a roaming event triggers the roaming applet on SIM.
ME to ICCANY : AO D6 00 00 OB
00 01 03 04 05 06 07 08 09 0A 0B
(implicit roaming detection when EFLOCI update by ME)
ICCNORMAL to ME: 90 00 (normal SIM)
ICCOLOLIDE to ME: 91 xx (Cloud SIM - see below)
The SIX applet wishes to determine the roaming partner by searching the preferred partner list in the current location.
STK applet selects the file with FID (as mentioned in 3GPP TS 51.011). Generally, file requests are handled by SIM OS by resolving address of the selected file in the local storage area. In the current invention, the FAT for Cloud Files includes special handling and hence the SIM-OS will resolve the address from a remote location.
The SIM OS requests assistance from Mobile browser via TLK interface like LAUNCH BROWSER or PROVIDE LOCATION INFO or SEND SMS / RECEIVE SMS . or any other toolkit interface relevantly adapted to current invention needs. Hence the SIM responds with 91 xx. In this example, Tlk Launch Browser is used for illustration.
e.g.: TikLaunchBrowser ("file:\\ftp.mobileoperator.com/roaminglist.rec %iocalinfo")

Note: the parameter list used above is only indicative
ME to ICCCLOUD :A0 12 00 00 45
ICCCLOUD to ME: DO 19 81 03 09 15 00 82 02 81 82 Bl 38 66 69 6C 65 3A 2F 2F 66 74 70 2E 6D 6F 62 69 6C 65 6F 70 65 72 61 74 6F 72 2E 63 6F 6D 2F 72 6F 61 6D 69 6E 67 6C 69 73 74 2E 72 65 63 20 25 6C 6F 63 61 6C 69 6E 66 6F 90 00
The browser then routes the requests for further handling, i.e., SD card file system or ftp or any other cloud data space. The "SIM Cloud server" component at the receiver end interprets and processes these requests accordingly.
In the current example, the server will return the list of partners applicable for "%locaiinfo" where the subscriber is currently in roaming.
The data from the relevant location is then passed back to the SIM via data in Terminal Response.
e.g:TerminalResponse(*abc, def, ghi")
ME to ICCCLOUD :A0 14 00 00 17
81 03 09 15 00 83 01 00 10 0D 61 62 63 2C 20 64
65 65 2C 20 67 68 69'
ICCCLOUD to ME: 90 00
For simplicity, the response data is showed as plain data. In practice it could be encrypted or plain based on sensitivity of the data.
The SIM STK now has the relevant information to process further.
Like any other toolkit feature, this feature is also dependant on the Mobile capabilities. Exceptions for handling the procedures in case of non-supported Mobife remain similar to the exception of other toolkit features and are not detailed in this document scope.

In the above example, the data is stored in an ftp server, and the data is shared by many subscribers. Depending on the usage scenario, the data can be available in SD card, phone memory, etc where the files are accessible by mobile browsers via url notations.
e.g.; file on SD card : file://sdcard/phonebook.rec
Persistent file on phone memory: file://c:/data/app/wallet.rec
RAM file on phone memory:
file://terminal/ramfile/log.txt
Example 2: SIM application accessing cloud files on mobile SD card
Typical SIM applet has User Interface in terms of Menu's and prompts messages wherever relevant. It is possible to support multilingual with having additional files to store these text messages, while the business logic remains same. More the number of languages supported, more space is required on the card. Typical a subscriber may have only one language preference; it may not be possible for the operator to know the preference at the time of early personalization. It is also difficult for the operator to reserve space for such information to be updated at later stage, since each language may take different file size depending on its script complexity.
To address above problem, a default language "English" is always available on SIM card in an EFENG- Additional Language info could be specified in EFASIAN which is set as a cloud file that is linked to user mobile's SD card space. Since the data stored in such files is trivial and also occupy more space.
In any instance, this file is not locatable by the SIM applet; the default file in SIM may be used.
The procedures remain same as explained in example 1.
(a) Handling of files by the SIM - How existing behaviour and proposed new behaviour is supported:

The handling of (local) files present on the SIM card is same for both existing behavior and proposed new behavior.

Terminal tries to select existing file on SIM Select File
A0 A4 00 00 02 6F 3A^
SIM responds Success ←9Fxx
The handling of external (or cloud) files is new for the proposed new behavior.

Terminal tries to select Select File
file on SIM AO A4 00 00 02 6F 3B→
SIM identifies that this
file is "remotely located"
SIM enters to master mode ←91 xx
Terminal awaits till SIM gets
back to slave mode
Terminal serves the request A0 12 00 00 XX
from slave
SIM mentions further action. ←D0
The path where the file is
Located
Terminal process the
Information and access the
File. -
Terminal provides the A0 14 00 00 YY
Information back to SIM
SIM responds Success for ←9Fxx
original file select from
Terminal
It may be noted that the highlighted portion is new for proposed new behavior.

This is further detailed in the beiow diagram (the handling of external (or cloud) files for the proposed new behavior):

Achievement of triggering of roaming applet on SIM:
There are different ways to trigger it, in most of the cases it is derived by the information based by the mobile handset to the SIM card.
Access to additional hardware on non-supported mobile devices:
As part of the SIM initialization procedure, the ME sends the profile download instruction to the SIM. The profile sent by the ME shall state the facilities relevant to capabilities that are supported by the ME. This procedure is specified in 3GPP TS 31.101.
Particular applications will not run on the SIM in non-supported mobiles.

Resource balancing is achieved by extended file management and extended toolkit management
The objective is to overcome the resource limitation on the existing SIM card, through the use of extended file management and extended toolkit management.
Hosting cloud storage for SIM in leased servers or through channel partners ?
The cloud storage for SIM is technically provided from any file server.
The mention of leased server/channel partner is to relate a business use case of how storage space provided on Cloud could also be chargeable.
Accessing cloud filed in a roaming applications:
It is the same as in the case of accessing cloud files on ftp server.
Explicit reference of roaming application is given to mention the need of such use case in real time.
It will be appreciated by those of ordinary skill in the art that the invention can be embodied in various specific forms without departing from its essential characteristics. The disclosed embodiments are considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the appended claims, rather than the foregoing description, and all changes that come within the meaning and range of equivalents thereof are intended to be embraced thereby.

WE CLAIM :
1. A method of extending the available memory of SIM / USIM / RUIM Card
using external memory available on network/terminal, the memory storage
location opted by the SIM application based on type of use, comprising the steps
of:
handling external files by SIM between Terminal and SIM during file selection involving:
terminal trying to select file on SIM;
SIM identifying that this file is "remotely located";
SIM entering to master mode;
terminal awaiting till SIM gets back to slave mode;
terminal serving the request from slave;
SIM mentioning further action;
terminal processing the information and accessing the file;
terminal providing the information back to SIM;and
SIM responding success for original file select from terminal.
2. The method as claimed in claim 1, wherein appropriate memory storage location that can be opted for by the SIM includes mobile memory for trivial and frequently accessed data that is required for the SIM application and is required only for the current session, e.g., cell broadcast data.
3. The method as claimed in claim 1, wherein appropriate memory storage location that can be opted for by the SIM includes external secure digital (SD) card memory for large and frequently accessed data, e.g., multi-language strings.
4. The method as claimed in claim 1, wherein appropriate memory storage location that can be opted for by the SIM includes terminal's memory pool, terminal's OR memory or MNO's hosted server (via terminal).

5. The method as claimed in claim 1, wherein appropriate memory storage location that can be opted for by the SIM includes Internet's public domain (via Terminal) data servers [for large and less frequently accessed data meant for sharing among user group].
6. The method as claimed in claims 1 to 5, wherein handling of external files by SIM between Terminal and SIM during file selection is as below:

Description Terminal SIM
Terminal tries to select file on SIM Select File
AO A4 00 00 02 6F 3B→
SIM identifies that this file is "remotely located"
SIM enters to master mode ←91 xx
Terminal awaits till SIM gets back to slave mode
Terminal serves the request from slave A0 12 00 00 XX
SIM mentions further action. The path where the file is Located ←D0
Terminal process the Information and access the File.
Terminal provides the Information back to SIM A0 14 00 00 YY
SIM responds Success for original file select from Terminal ←9Fxx
.7. The method as claimed in claims 1 to 6, wherein the handling of external (or cloud) files for the proposed new behavior is as under:

Terminal tries to select file on SIM Select File
A0 A4 00 00 02 6F 3B→
SIM identifies that this file is "remotely located"
SIM enters to master mode ←91 xx
Terminal awaits till SIM gets back to slave mode
Terminal serves the request from slave A0 12 00 00 XX
SIM mentions further action. The path where the file is Located ←D0
Terminal process the Information and access the File.
Terminal provides the Information back to SIM A0 14 00 00 YY

SIM responds Success for ←9Fxx
original file select from
Terminal
8. The method as claimed in claims 1 to 7, wherein-SIM cards with different capabilities are provided (Java / native, GSM / CDMA).
9. The method as claimed in claims 1 to 8, wherein delivery platforms are provided to mobile operators for the launch of value-added-services.
10. The method as claimed in claims 1 to 9, wherein Trusted Services (TSM) are provided to banks, retailers as well as mobile operators.
11. The method as claimed in claims 1 to 10, wherein the Cloud Storage for SIM as a service could be hosted in G&D 3S servers or through channel partners.
12. The method as claimed in claims 1 to 11, wherein the Cloud Storage that is hosted in G&D 3S servers are leased.
13. The method as claimed in claims 1 to 12, wherein data storage can also be charged based on pay-per-use model.
14. The method as claimed in claims 1 to 9, wherein fee based usage of data / services can be shared by different subscribers.