Description

SIM cards have to main categories CDMA / GSM here i am focus on GSM SIM cards. This cards have two types of charging system PREPAID and POSTPAID.

The format of the ICCID is: MMCC IINN NNNN NNNN NN C x

MM = Constant (ISO 7812 Major Industry Identifier)

CC = Country Code

II = Issuer Identifier

N{12} = Account ID ("SIM number")

C = Checksum calculated from the other 19 digits using the Luhn algorithm.

x = An extra 20th digit is returned by the 'AT!ICCID?' command, but it is not officially part of the ICCID.

PREPAID

Prepaid cards already have a tax plan assigned to them

POSTPAID

SIM Card Structure

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SIM cards hold a profile mapped by the network operator, these cards have a storage capacity 8k,16k,32k128k,etc...

MF - Master Files

DF - Dedicated Files

EF - Elementary Files

Standards : GSM 11.11 - 3GPP 51.011

SIM Card Profile

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Network Requirements

• MCC / MNC

• IMSI

• ICC-ID

• SMS Parameters

Marketing Requirements

• Phonebook

• Number of Short Messages

• Service Dialing Number (Customer Care Numbers

• Mailbox Number

Business Requirements

• Roaming Partner List

• PIN Handling

ICC-ID

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ICC

• SIM - Single IMSI or Dual IMSI

• RUIM - Single CDMS or Combo CDMA+GSM

ICC-ID is defined by ITU-T E.118

The ICC-ID has 19 digits and calculated using Luhn algorithm.

89-91-15-100-000000011-8

89 - Tele

91 - CC

15 - MNC

100 - Vendor

000000011 - Serial Number

8 - Checksum

IMSI

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International Mobile Subscriber Identity

The IMSI has 15 digits and is unique across all globe and indicates the home network of the subscriber.

MCC + MNC + MSIN = IMSI

MNS + MSIN = NMSI

SIM Keys