Transcript PowerPoint 프레젠테이션

3. Smart Identification
3.1 Smart Cards
3.1.1 What Is a Smart Card?
 Smart cards evolved from plastic identification and magnetic stripe cards through
adding a secure, tamper-resistant single-chip microcomputer.
 In the tasks of very reliable authentication, electronic signature generation, and
cryptograph, smart cards are superior to traditional magnetic stripe technologies.
 A patent for an identification card with an integrated circuit was filed, and the smart
card was born (1968).
 An important characteristic of a smart card is that the information on it cannot be copied.
 Smart cards are recognized as the next generation financial transaction cards.
 Today every mobile phone that complies with the GSM standard contains a smart card
that identifies the phone and authenticates the owner to the telephone system.
 Building access system, home banking applications
1
 Magnetic Card & Smart Card
Type
Magnetic Card
Smart Card
용량
150~800 bit
64 Kbit
1 Kbit 당 가격
20 Cent
24 Cent
보안
정보변경이 쉽다.
신분증명
4 자리 숫자
정보 변경이 어렵다.
자체 검증 기능이 있다.
숫자, 문자, 지문 등 신체
특성 사용이 기능
외부교신
자기
전기
장점
싸고, 널리 손쉽게 사용 중
보안 기능과 다양한 응용
분야
단점
보안성이 취약
용량이 제한적
자기 손상 가능
값이 비싸다.
2
 Smart Card Classification
Smart Cards
Components
Interface
OS Used
Memory
Contact
JavaCard
Chip
Contactless
Multos
Hybrid
3
3.1.2 Smart Card Hardware
3.1.2.1 Contact and Contactless Cards
 Communication can take place either through the contacts on the card or via wireless
(“contactless”) transmission.
3.1.2.2 The Computer on the Smart Card
 The chip of a smart card consists of a microprocessor, ROM, EEPROM, and RAM.
ROM (16 kb)
- Operating System
- Communication
- Security (DES, RSA)
CPU
- 8 bit
- 5 MHz, 5V
- Optional: cryptocoprocessor
EEPROM (16 kb)
- File system
- Program files
- Keys
- Passwords
- Applications
RAM
- 4 kb
4
 Standards: ISO 7816
Desig
nation
Use
Vcc
Power connection through which operating power is
supplied to the microprocessor chip in the card
RST
Reset line through which the IFD can signal to the
smart card's microprocessor chip to initiate its reset
sequence of instructions
CLK
Clock signal line through which a clock signal can be
provided to the microprocessor chip. This line controls
the operation speed and provides a common
framework for data communication between the IFD
and the ICC
RFU
Reserved for future use
GND
Ground line providing common electrical ground
between the IFD and the ICC
Vpp
Programming power connection used to program
EEPROM of first generation ICCs.
I/O
Input/output line that provides a half-duplex
communication channel between the reader and the
smart card
RFU
Reserved for future use
5
3.1.2.3 Hardware Security
 The objective of smart card chip design is to provide high physical security for the data
stored in the card.
 These include slicing off layers of the chip to optically read out data, manipulating the
voltage or clock to make the processor fail, attacks through using high temperature or Xrays, and several others.
3.1.2.4 Card Acceptance Devices
 Many pervasive devices like set-top boxes, cellular phones, or handhelds are equipped
with smart card readers.
3.1.3 Smart Card Software
 The off-card part of the application is the part that resides on the host computer or
terminal connected to the smart card through a smart reader device.
예) OCF(OpenCard Framework)
6
 The on-card application is a program stored in the memory of the smart card chip. If the
on-card application has executable code, this code is executed by the smart card
operating system and can use operating system services, such as encrypting or
decrypting data. These functions can be used to make the smart card and the
communication with the smart card very secure.
 The majority of current cards have a file system integrated into the operating system.
 ISO 7816 File System
MIF
 A file system consists of directory (DF) and
files (EF). The root directory is referred as
MF.
DF
 MF (Master File)
EF
DF(Dedicated File)
DF
EF(Elementary File)
EF
DF
7
 Recently developed card operating systems enable application developers to create and
download on-card application code on their own. The most important of these operating
systems are Java Card and Multos.
3.1.4 Communication Between the On-Card and Off-Card Parts
3.1.4.1 Application Protocol Data Unit (APDU)
 Application Protocol Data Units are used to exchange data between the host and the
smart card.
 ISO 7816-4 defines two types of APDUs: Command APDUs, which are sent from the
off-card application to the smart card, and Response APDUs, which are sent back from
the smart card to reply to commands.
 Command APDU
CLA
INS
P1
P2
Lc
Optinal Data
Le
8
 Response APDU
Optional Data
SW1
SW2
3.1.4.2 Protocol Layer
 The protocol with T=0, each character is transmitted separately, while with T=1, blocks
of characters are transmitted.
3.2 Smart Labels
 Bar codes
 Advantages
 They can be printed on labels, they are very inexpensive, and they can be reliably scanned.
 Disadvantages
 Since bar code are scanned optically, they must be visible on the outside of the object.
 Scanning takes place at a short range – a few centimeters.
9
 The objects must be separated in order to be identified.
 The information conveyed by a bar code is fixed when the bar code is printed and cannot be
changed.
 The bar code itself is completely passive and any bar code reader can access its information,
making it very difficult to fulfill security requirements demanded by some applications.
 The bar code scanners are complicated – typically involving a laser, moving mirrors, and
detection hardware – making them expensive.
 Smart Label Block Diagram, p. 58
 An RF antenna captures the radio waves and special circuitry on the chip converts the
radio frequency energy to appropriate voltage.
 Communication between reader and smart label takes place using open communication
protocols at a frequency of 13.56 MHz. Data is typically transferred at a rate of 26 kbps,
although faster speeds are possible.
 Through use of collision avoidance algorithms, several smart labels can be accessed
simultaneously.
10
 예 – Texas Instruments Tag-it smart label inlays
 Smart labels contain control logic with non-volatile read/write memory for data storage.
Data capacity ranges from 64 bits to about 2K bits.
 The smart label has a pre-programmed unique serial number plus storage for a userprogrammable secret key. To test for validity of the smart label, the reader sends a
command containing a random number to the smart label. The smart label encrypts the
random number and returns it along with its unique serial number. The reader decrypts
the message using the key associated with the serial number and verifies that it is the
same as the random number sent.
11
3.2.1 Example Applications
 전자 물품 감시, EAS(Electronic Article Surveillance) field
 Shipping industry
 The smart label contains identification and destination information.
 Inventory control
3.3 Smart Tokens
 The need for robustness can be fulfilled by encapsulating the chips in plastic or metal.
 Examples – tollbooth, gas station, security system
3.3.1 Smart Token Examples
 Key fob from Gemplus
12
 The chip contains 1024 bytes of EEPROM memory chip and associated antenna.
 iButton
 iButtons can contain microprocessor chips or memory chips.
 A cryptographic chip implementing the JavaCard 2.0 Standard is also available.
13