Difference between pages "Microsoft PocketPC" and "SIM Cards"

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[[Image:Simpic.jpg|thumb|A typical SIM card.]]
  
=Overview=
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== SIM-Subscriber Identity Module ==
A PocketPC is commonly referred to as a handheld computer that runs a version of Microsoft’s proprietary mobile operating systems.
+
  
[[Image:Pocketpc.jpg|thumb|Acer PocketPC]]
+
The UICC (Universal Integrated Circuit Card) is a smart card which contains account information and memory that is used to enable GSM cellular telephones.  One of the applications running on the smart card is the SIM, or Subscriber Identity Module. In common parlance the term "UICC" is not used an the phrase "SIM" is used to describe the smart card itself.
  
Microsoft PocketPC, sometimes referred to as P/PC or PPC, is based upon the Windows CE framework.  Variants of this operating system include versions such as PocketPC 2000, PocketPC 2002, Windows Mobile 2003/2003 SE, and Windows Mobile 5.0. Variants also exist for [[SmartPhones]], such as Windows Mobile 2003 Smartphone edition.
+
Because the SIM is just one of several applications running on the smart card, a given card could, in theory, contain multiple SIMs. This would allow multiple phone numbers or accounts to be accessed by a single UICC. This is seldom seen, though there is at least one "12-in-1" SIM card being advertised at present.
  
One of the key benefits of Microsoft's Windows Mobile platform is file format compatibility with the desktop versions of the company's productivity softwareMobile versions of Microsoft software, such as Microsoft Word, Excel, and PowerPoint, allow individuals to view and edit these files outside of the home and office.  
+
Early versions of the UICC used full-size smart cards (85mm x 54mm x 0.76mm)The card has since been shrunk to the standard size of 25mm x 15mm x 0.76mm.
  
Another benefit is integration with Microsoft's cross-platform solution, the .NET Framework.  The .NET Framework and its associated class libraries handle things such as memory management, file I/O, and many other functions.  The .NET Framework allows programmers to develop code in one of several .NET languages, such as C# and VB.NET.  PocketPCs run a simplified version of the framework called the .NET Compact Framework.
 
  
In order to maintain synchronization and connectivity with desktop computers, Microsft developed the ActiveSync program.  The user merely has to connect the PocketPC to the desktop computer in order to synchronize items such as appointments, contact lists, and even multimedia files.
+
Although UICC cards traditionally held just 16 to 64KB of memory, the recent trend has been to produce SIM cards with larger storage capacities, ranging from 512MB up to [http://www.m-systems.com/site/en-US/ M-Systems'] 1GB SIM Card slated for release in late 2006.
  
In 2001, PDAs running Palm OS variants held a market share of about 72%, while PocketPC held a meager 15% of the market.  However, by the fourth quarter of 2004, Microsoft PocketPC and Palm OS were practically tied with regards to market share -- PocketPC-based devices had a market share of 40.2% while Palm OS claimed 40.7% of the market.  This upward trend clearly illustrates the growing popularity of PocketPC-based devices, and thus the increased likelihood that one will encounter such a device in the field.
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== ICCID ==
  
 +
Each SIM is internationally identified by its ICC-ID (Integrated Circuit Card ID). ICC-IDs are stored in the SIM card and can also be engraved or printed on the SIM card’s body during a process called personalization. The number is up to 18 digits long with an addition of a single “check digit” that is used for error detection.  This single digit allows us to detect an input error of digits, mistyped digits or a permutation of two successive digits.  This digit was calculated using the Luhn algorithm.
  
== History ==
+
A typical SIM (19 digits) example 89 91 10 1200 00 320451 0, provide several details as follows:
  
The PocketPC operating system began as Windows CE in November of 1996. The NEC MobilePro 200 and the Casio A-10 were the first two PDA-type devices available with this early version of the operating system. From here, Windows CE continued in development through versions 2 (with such devices as the MD Elan SC400, DEC SA1100, Hitachi SuperH 3, NEC VR4101, Philips DR 31500, and the Toshiba TX3912).
+
*The first two digits (89 in the example) refers to the Telecom Id.
 +
*The next two digits (91 in the example) refers to the country code (91-India).
 +
*The next two digits (10 in the example) refers to the network code.
 +
*The next four digits (1200 in the example) refers to the month and year of manufacturing.
 +
*The next two digits (00 in the example) refers to the switch configuration code.
 +
*The next six digits (320451 in the example) refers to the SIM number.
 +
*The last digit which is separated from the rest is called the “check digit”.
  
=PocketPC Variants=
 
As previously noted, there exist many variants of the PocketPC operating system.  Below are a summary of each.
 
  
==PocketPC 2000==
+
These digits can be further grouped for additional information:
 +
*The first 3 to 4 digits represents the Mobile Country Code (MCC)(Some cards only have 3 digits to represent the Telecom ID and country code.)
 +
*The next 2 digits represent the Mobile Network Code (MNC, AKA the mobile operator)
 +
*The next 12 digits is the number represent the Home Location Register
 +
*And mentioned above, the “check digit”
  
 +
== Location Area Identity==
  
==PocketPC 2002==
+
Operation networks for cell phone devices are divided into area locations called Location Areas.  Each location is identified with its own unique identification number creating the LAI (Location Area Identity).  A phone will store this number on its SIM card so it knows what location it’s in and to be able to receive service.  If a phone were to change to a new Location Area, it stores the new LAI in the SIM card, adding to a list of all the previous LAIs it has been in. This way if a phone is powered down, when it boots back up, it can search its list of LAIs it has stored until it finds the one its in and can start to receive service again. This is much quicker than scanning the whole list of frequencies that a telephone can have access on
Pocket PC 2002, Microsoft's PDA operating system, is more stable than the previous version and offers a barrel of bundled software, including MSN Messenger and a remote access client. However in order to run this operating system, serious hardware requirements must be available. Flash ROM is one of the requirements which only comes standard on the Compaq Ipaq.
+
This is a real plus for forensic investigators because when a SIM card is reviewed, they can get a general idea of where the SIM card has been geographically.  In turn this tells them where the phone has been and can then relate back to where the individual who owns the phone has been.  
  
==Windows Mobile 2003/SE==
+
== SIM Security ==
Based on the Windows CE.Net operating system, Windows Mobile 2003 for Pocket PC includes a Windows-like graphical user interface (GUI), tools and helper apps, and several companion applications, including Pocket Word and Pocket Excel. It's the third major release of the platform, which debuted in April 2000 and was last updated in October 2001
+
  
Here's a list of Windows Mobile 2003 for Pocket PC's new features:
+
Information inside the UICC can be protected with a PIN and a PUK.
  
-- Enhanced Connection Manager user interface
+
A PIN locks the SIM card until correct code is entered. Each phone network sets the PIN of SIM to a standard default number (this can be changed via handset). If PIN protection is enabled, the PIN will need to be entered each time phone is switched on. If the PIN is entered incorrectly 3 times in a row, the SIM card will be blocked requiring a PUK from the network/service provider.
+
-- Zero Configuration connections
+
+
-- Improved animated connectivity status icons
+
+
-- Improved connectivity bubbles
+
  
-- Always-on Bluetooth discoverability
+
A PUK is needed if the PIN is entered incorrectly 3 times and the SIM is blocked (phone is unable to make and receive calls/texts). The PUK can be received from the network provider, or possibly the GSM cell phone manual. '''Caution:''' if PUK is entered 10 times incorrectly, the SIM card is permanently disabled and must be exchanged.
+
-- Use of Bluetooth modems
+
  
-- Bluetooth beaming
+
== SIM Forensics ==
  
-- Auto-correct spelling
+
The data that a SIM card can provide the forensics examiner can be invaluable to an investigation. Acquiring a SIM card allows a large amount of information that the suspect has dealt with over the phone to be investigated.
+
-- Auto-suggest in Inbox
+
  
-- One-touch turn all radios off
+
In general, some of this data can help an investigator determine:
+
* Phone numbers of calls made/received
-- 802.1x support
+
* Contacts
 +
* [[SMS]] details (time/date, recipient, etc.)
 +
* SMS text (the message itself)
  
-- Certificate Management UI
+
There are many software solutions that can help the examiner to acquire the information from the SIM card. Several products include 3GForensics SIMIS [http://www.3gforensics.co.uk/products.htm], Inside Out's [http://simcon.no/ SIMCon], or SIM Content Controller, and Paraben Forensics' [http://www.paraben-forensics.com/catalog/product_info.php?products_id=289 SIM Card Seizure].
  
-- IPSec/L2TP
+
The SIM file system is hierarchical in nature consisting of 3 parts:
 +
*Master File (MF) - root of the file system that contains
 +
DF’s and EF’s
 +
*Dedicated File (DF)
 +
*Elementary Files (EF)
  
-- Support for Multiple VPNs
 
 
-- IPv6 support
 
 
-- New Today screen
 
 
-- Smart Lookup in Contacts
 
 
-- Windows CE 4.2 operating systems
 
 
-- .NET Compact Framework
 
 
-- Enhanced developer support
 
 
-- 128-bit encryption strength for Crypto API
 
 
-- Improved power management
 
 
-- Windows Media Player 9 Series for Pocket PC 2003
 
 
-- Plus! Sync & Go
 
  
-- Support for Plus! Photo Story
+
=== Data Acquisition ===
+
-- Windows Movie Maker 2
+
  
-- Pictures
+
These software titles can extract such technical data from the SIM card as:
  
-- New version of Pocket Internet Explorer
+
* '''International Mobile Subscriber Identity (IMSI)''': A unique identifying number that identifies the phone/subscription to the [[GSM]] network
+
* '''Mobile Country Code (MCC)''': A three-digit code that represents the SIM card's country of origin
-- "Jawbreaker" game
+
* '''Mobile Network Code (MNC)''': A two-digit code that represents the SIM card's home network
+
* '''Mobile Subscriber Identification Number (MSIN)''': A unique ten-digit identifying number that identifies the specific subscriber to the GSM network
-- vCard and vCal support
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* '''Mobile Subscriber International ISDN Number (MSISDN)''': A number that identifies the phone number used by the headset
 +
* '''Abbreviated Dialing Numbers (ADN)''': Telephone numbers stored in sims memory
 +
* '''Last Dialed Numbers (LDN)'''
 +
* '''Short Message Service (SMS)''': Text Messages
 +
* '''Public Land Mobile Network (PLMN) selector'''
 +
* '''Forbidden PLMNs'''
 +
* '''Location Information (LOCI)'''
 +
* '''General Packet Radio Service (GPRS) location'''
 +
* '''Integrated Circuit Card Identifier (ICCID)'''
 +
* '''Service Provider Name (SPN)'''
 +
* '''Phase Identification'''
 +
* '''SIM Service Table (SST)'''
 +
* '''Language Preference (LP)'''
 +
* '''Card Holder Verification (CHV1) and (CHV2)'''
 +
* '''Broadcast Control Channels (BCCH)'''
 +
* '''Ciphering Key (Kc)'''
 +
* '''Ciphering Key Sequence Number'''
 +
* '''Emergency Call Code'''
 +
* '''Fixed Dialing Numbers (FDN)'''
 +
* '''Forbidden PLMNs'''
 +
* '''Local Area Identitity (LAI)'''
 +
* '''Own Dialing Number'''
 +
* '''Temporary Mobile Subscriber Identity (TMSI)'''
 +
* '''Routing Area Identifier (RIA) netowrk code'''
 +
* '''Service Dialing Numbers (SDNs)'''
 +
* '''Service Provider Name'''
 +
* '''Depersonalizatoin Keys'''
  
-- Inbox signature support
+
This information can be used to contact the service provider to obtain even more information than is stored on the SIM card.
+
-- New user notifications
+
  
==Windows Mobile 5.0==
+
== USIM-Universal Subscriber Identity Module ==
Windows Mobile 5.0, based off of Windows CE 5.0, was released on May 10, 2005.  Windows Mobile 5.0 brought many changes to the PocketPC landscape.  For one, with this release, the phone and PDA versions of the OS have merged into one encompassing OS, instead of two separate versions of the same one.  Additionally, while past versions of PocketPC software utilized the RAM of a PDA for program and data storage, Windows Mobile 5.0 uses a PDA's hardware more like a traditional computer.  The operating system and user data is stored in the more persistent ROM of the device, and RAM is used in a way more similar to that of a desktop PC.  This has implications for forensics, as data stored on these devices is now less volatile.
+
  
 +
A Universal Subscriber Identity Module is an application for UMTS mobile telephony running on a UICC smart card which is inserted in a 3G mobile phone. There is a common misconception to call the UICC card itself a USIM, but the USIM is merely a logical entity on the physical card.
  
=Pocket PC Devices=
+
It stores user subscriber information, authentication information and provides storage space for text messages and phone book contacts. The phone book on a UICC has been greatly enhanced.
In recent years, a number of manufacturers have elected to produce PocketPC devices. Some of these makers include companies such as:
+
  
*  Audiovox
+
For authentication purposes, the USIM stores a long-term preshared secret key K, which is shared with the Authentication Center (AuC) in the network. The USIM also verifies a sequence number that must be within a range using a window mechanism to avoid replay attacks, and is in charge of generating the session keys CK and IK to be used in the confidentiality and integrity algorithms of the KASUMI block cipher in Universal Mobile Telecommunications System (UMTS).
*  Dell
+
*  HP
+
*  Mitac
+
*  Motorola
+
*  Samsung
+
*  Siemens
+
*  Symbol
+
  
Because different manufacturers are targeted at different segments of the market, such as business and consumers, the features and functionality of these devices sometimes differ greatly. For example, some devices have built-in capability for taking images and videos, while other devices have tools such as biometric fingerprint readers and barcode scanners.
+
In Mobile Financial Services, USIM seems to be a mandetory Security Element for user authentication, authorization and stored credentials. With the integration of NFC Handset and USIM, users will be able to make proximity payments where the NFS handset enables contactless payment and USIM enables independent security element.
 +
This is the evolution of the SIM for 3G devices. It can allow for multiple phone numbers to be assigned to the USIM, thus giving more than one phone number to a device.
  
 +
== Service Provider Data ==
  
 +
Some additional information the service provider might store:
  
 +
* A customer database
 +
* [[Call Detail Record]]s (CDR)
 +
* [[Home Location Register]] (HLR)
  
  
'''References:'''
+
== Service Providers that use SIM Cards in the United States ==
----
+
* T-Mobile
 +
* Cingular/AT&T
  
[http://www.hpcfactor.com/support/windowsce/ The History of Microsoft Windows CE]
+
== Sim Card Text Encoding ==
  
[http://palmtops.about.com/cs/pdafacts/a/Palm_Pocket_PC.htm Palm vs. Pocket PC-The Great Debate]
+
Originally the middle-European [[GSM]] network used only a 7-bit code derived from the basic [[ASCII]] code. However as GSM spread worldwide it was concluded that more characters, such as the major characters of all living languages, should be able to be represented on GSM phones. Thus, there was a movement towards a 16-bit code known as [[UCS-2]] which is now the standard in GSM text encoding. This change in encoding can make it more difficult to accurately obtain data form [[SIM cards]] of the older generation which use the 7-bit encoding. This encoding is used to compress the hexadecimal size of certain elements of the SIMs data, particularly in [[SMS]] and [[Abbreviated Dialing Numbers]].
  
[http://www.windowsfordevices.com/news/NS8063885791.html Gartner: Windows CE ties Palm]
+
== Authentication Key (Ki) ==
 +
The authentication key or Ki is a 128 bit key used in the authentication and cipher key generation process. In a nutshell, the key is used to authenticate the SIM on the GSM network. Each SIM contains this key which is assigned to it by the operator during the personalization process. The SIM card is specially designed so the Ki can't be compromised using a smart-card interface. However, flaws in the GSM cryptography have been discovered that do allow the extraction of the Ki from the SIM card, and essentially SIM card duplication.
  
[http://en.wikipedia.org/wiki/Pocket_PC PocketPC]
+
== See also ==
 +
 
 +
* [[SIM Card Forensics]]
 +
 
 +
== References ==
 +
 
 +
* [http://www.simcon.no/ SIMCon]
 +
* [http://www.sectorforensics.co.uk/sim-examination.shtml Sector Forensics]
 +
* [http://www.utica.edu/academic/institutes/ecii/ijde/articles.cfm?action=issue&id=5  IJDE Spring 2003 Volume 2, Issue 1 ]: [http://www.utica.edu/academic/institutes/ecii/publications/articles/A0658858-BFF6-C537-7CF86A78D6DE746D.pdf Forensics and the GSM Mobile Telephone System] (PDF)
 +
* http://en.wikipedia.org/wiki/Subscriber_Identity_Module

Revision as of 07:58, 29 September 2008

A typical SIM card.

SIM-Subscriber Identity Module

The UICC (Universal Integrated Circuit Card) is a smart card which contains account information and memory that is used to enable GSM cellular telephones. One of the applications running on the smart card is the SIM, or Subscriber Identity Module. In common parlance the term "UICC" is not used an the phrase "SIM" is used to describe the smart card itself.

Because the SIM is just one of several applications running on the smart card, a given card could, in theory, contain multiple SIMs. This would allow multiple phone numbers or accounts to be accessed by a single UICC. This is seldom seen, though there is at least one "12-in-1" SIM card being advertised at present.

Early versions of the UICC used full-size smart cards (85mm x 54mm x 0.76mm). The card has since been shrunk to the standard size of 25mm x 15mm x 0.76mm.


Although UICC cards traditionally held just 16 to 64KB of memory, the recent trend has been to produce SIM cards with larger storage capacities, ranging from 512MB up to M-Systems' 1GB SIM Card slated for release in late 2006.

ICCID

Each SIM is internationally identified by its ICC-ID (Integrated Circuit Card ID). ICC-IDs are stored in the SIM card and can also be engraved or printed on the SIM card’s body during a process called personalization. The number is up to 18 digits long with an addition of a single “check digit” that is used for error detection. This single digit allows us to detect an input error of digits, mistyped digits or a permutation of two successive digits. This digit was calculated using the Luhn algorithm.

A typical SIM (19 digits) example 89 91 10 1200 00 320451 0, provide several details as follows:

  • The first two digits (89 in the example) refers to the Telecom Id.
  • The next two digits (91 in the example) refers to the country code (91-India).
  • The next two digits (10 in the example) refers to the network code.
  • The next four digits (1200 in the example) refers to the month and year of manufacturing.
  • The next two digits (00 in the example) refers to the switch configuration code.
  • The next six digits (320451 in the example) refers to the SIM number.
  • The last digit which is separated from the rest is called the “check digit”.


These digits can be further grouped for additional information:

  • The first 3 to 4 digits represents the Mobile Country Code (MCC)(Some cards only have 3 digits to represent the Telecom ID and country code.)
  • The next 2 digits represent the Mobile Network Code (MNC, AKA the mobile operator)
  • The next 12 digits is the number represent the Home Location Register
  • And mentioned above, the “check digit”

Location Area Identity

Operation networks for cell phone devices are divided into area locations called Location Areas. Each location is identified with its own unique identification number creating the LAI (Location Area Identity). A phone will store this number on its SIM card so it knows what location it’s in and to be able to receive service. If a phone were to change to a new Location Area, it stores the new LAI in the SIM card, adding to a list of all the previous LAIs it has been in. This way if a phone is powered down, when it boots back up, it can search its list of LAIs it has stored until it finds the one its in and can start to receive service again. This is much quicker than scanning the whole list of frequencies that a telephone can have access on. This is a real plus for forensic investigators because when a SIM card is reviewed, they can get a general idea of where the SIM card has been geographically. In turn this tells them where the phone has been and can then relate back to where the individual who owns the phone has been.

SIM Security

Information inside the UICC can be protected with a PIN and a PUK.

A PIN locks the SIM card until correct code is entered. Each phone network sets the PIN of SIM to a standard default number (this can be changed via handset). If PIN protection is enabled, the PIN will need to be entered each time phone is switched on. If the PIN is entered incorrectly 3 times in a row, the SIM card will be blocked requiring a PUK from the network/service provider.

A PUK is needed if the PIN is entered incorrectly 3 times and the SIM is blocked (phone is unable to make and receive calls/texts). The PUK can be received from the network provider, or possibly the GSM cell phone manual. Caution: if PUK is entered 10 times incorrectly, the SIM card is permanently disabled and must be exchanged.

SIM Forensics

The data that a SIM card can provide the forensics examiner can be invaluable to an investigation. Acquiring a SIM card allows a large amount of information that the suspect has dealt with over the phone to be investigated.

In general, some of this data can help an investigator determine:

  • Phone numbers of calls made/received
  • Contacts
  • SMS details (time/date, recipient, etc.)
  • SMS text (the message itself)

There are many software solutions that can help the examiner to acquire the information from the SIM card. Several products include 3GForensics SIMIS [1], Inside Out's SIMCon, or SIM Content Controller, and Paraben Forensics' SIM Card Seizure.

The SIM file system is hierarchical in nature consisting of 3 parts:

  • Master File (MF) - root of the file system that contains

DF’s and EF’s

  • Dedicated File (DF)
  • Elementary Files (EF)


Data Acquisition

These software titles can extract such technical data from the SIM card as:

  • International Mobile Subscriber Identity (IMSI): A unique identifying number that identifies the phone/subscription to the GSM network
  • Mobile Country Code (MCC): A three-digit code that represents the SIM card's country of origin
  • Mobile Network Code (MNC): A two-digit code that represents the SIM card's home network
  • Mobile Subscriber Identification Number (MSIN): A unique ten-digit identifying number that identifies the specific subscriber to the GSM network
  • Mobile Subscriber International ISDN Number (MSISDN): A number that identifies the phone number used by the headset
  • Abbreviated Dialing Numbers (ADN): Telephone numbers stored in sims memory
  • Last Dialed Numbers (LDN)
  • Short Message Service (SMS): Text Messages
  • Public Land Mobile Network (PLMN) selector
  • Forbidden PLMNs
  • Location Information (LOCI)
  • General Packet Radio Service (GPRS) location
  • Integrated Circuit Card Identifier (ICCID)
  • Service Provider Name (SPN)
  • Phase Identification
  • SIM Service Table (SST)
  • Language Preference (LP)
  • Card Holder Verification (CHV1) and (CHV2)
  • Broadcast Control Channels (BCCH)
  • Ciphering Key (Kc)
  • Ciphering Key Sequence Number
  • Emergency Call Code
  • Fixed Dialing Numbers (FDN)
  • Forbidden PLMNs
  • Local Area Identitity (LAI)
  • Own Dialing Number
  • Temporary Mobile Subscriber Identity (TMSI)
  • Routing Area Identifier (RIA) netowrk code
  • Service Dialing Numbers (SDNs)
  • Service Provider Name
  • Depersonalizatoin Keys

This information can be used to contact the service provider to obtain even more information than is stored on the SIM card.

USIM-Universal Subscriber Identity Module

A Universal Subscriber Identity Module is an application for UMTS mobile telephony running on a UICC smart card which is inserted in a 3G mobile phone. There is a common misconception to call the UICC card itself a USIM, but the USIM is merely a logical entity on the physical card.

It stores user subscriber information, authentication information and provides storage space for text messages and phone book contacts. The phone book on a UICC has been greatly enhanced.

For authentication purposes, the USIM stores a long-term preshared secret key K, which is shared with the Authentication Center (AuC) in the network. The USIM also verifies a sequence number that must be within a range using a window mechanism to avoid replay attacks, and is in charge of generating the session keys CK and IK to be used in the confidentiality and integrity algorithms of the KASUMI block cipher in Universal Mobile Telecommunications System (UMTS).

In Mobile Financial Services, USIM seems to be a mandetory Security Element for user authentication, authorization and stored credentials. With the integration of NFC Handset and USIM, users will be able to make proximity payments where the NFS handset enables contactless payment and USIM enables independent security element. This is the evolution of the SIM for 3G devices. It can allow for multiple phone numbers to be assigned to the USIM, thus giving more than one phone number to a device.

Service Provider Data

Some additional information the service provider might store:


Service Providers that use SIM Cards in the United States

  • T-Mobile
  • Cingular/AT&T

Sim Card Text Encoding

Originally the middle-European GSM network used only a 7-bit code derived from the basic ASCII code. However as GSM spread worldwide it was concluded that more characters, such as the major characters of all living languages, should be able to be represented on GSM phones. Thus, there was a movement towards a 16-bit code known as UCS-2 which is now the standard in GSM text encoding. This change in encoding can make it more difficult to accurately obtain data form SIM cards of the older generation which use the 7-bit encoding. This encoding is used to compress the hexadecimal size of certain elements of the SIMs data, particularly in SMS and Abbreviated Dialing Numbers.

Authentication Key (Ki)

The authentication key or Ki is a 128 bit key used in the authentication and cipher key generation process. In a nutshell, the key is used to authenticate the SIM on the GSM network. Each SIM contains this key which is assigned to it by the operator during the personalization process. The SIM card is specially designed so the Ki can't be compromised using a smart-card interface. However, flaws in the GSM cryptography have been discovered that do allow the extraction of the Ki from the SIM card, and essentially SIM card duplication.

See also

References