Dongguan Hele Electronics Corporation

Model Number: Professional mobile GSM SIM Card Brand Name: GRcard Key Specifications/Special Features: Specifications:1. GSM SIM card, T-Mobile SIM cards2. Can write IMSI, ICCID, SID, NID, PIN, PUK AMD, AKEY, SMSC technological information into card SIM card introduction2.1 Structure and typeSIM card is a smart card with a microprocessor and it consists of the following modules:CPUProgram memory (ROM)Working memory (RAM)

Data memory (EPROM or E2PROM)

Serial communication module

These five modules must be integrated into an integrated circuit (IC), otherwise their safety would be threatened
This is because the chip connections may become illegal access and misappropriation of SIM cards important clues
In practice, there are two different forms of SIM cards with the same functions:
(A) Full-size SIM card (commonly known as big card), this form of SIM cards with the IC cards of the ISO 7816 Standard [ISO7816], similar to IC card
The card has since been shrunk to the standard size of 25mm x 15mm
(B) Embedded SIM card (commonly known as small card), the size of only 25 mm x 15 mm, is a semi-permanent packed to the cards in the mobile station equipment
Two cards have installed waterproof, wear-resistant, anti-static contact with high accuracy and reliability characteristics
2.2 Cryptographic algorithm and secret key in SIM card
The most sensitive information of SIM card is the cryptographic algorithm A3, A8, secret Ki, PIN, PUK and Kc
A3, A8 algorithm were written into the SIM card in the producing process, and most people could not read A3, A8 algorithm
HN code could be settled by the phone owners
PUK code is held by the operator
Kc was derived in the process of encryption from Ki
PIN and PUK:

• PIN: personal identification number
• 2 PINs exist (PIN 1 and PIN 2)
• Limited attempts on PIN access
• PUK –PIN Unblocking Code
• Resetting PUK, resets PIN and the attempt counter
• Too many attempts on PUK blocks use permanently

The following tables describe the two phases of SIM card in GSM:
(1) Phase 1 GSM system parameters
Table 2-1 system parameter data options in phase 1
Identifier
Name
Length
6FAD
Administrative
3
6F38
Service table
4
6F07
IMSI
9
6F7B
Forbidden PLMN
12
6F7E
TMSI LAI
11
6F20
Kc, n
9
6F30
PLMN selector
24
6F74
BCCH information
16
6F78
Access control 2
Service 1: PIN disabling
Service 2: Abbreviated dialing numbers
Service 4: Short message storage
Service 6: Capability configuration parameters
Service 7: PLMN selector