Siemens Matcher on Card Version 1.1
| Smart cards offer the chance
to implement highly secured systems. Especially asymmetric encryption systems
which have to store the private key in a secure environment often are based
on smart cards with integrated crypto processor. Such cards will gain increasing
attention with the arrival of the electronic signature. The electronic
signature which is mainly understood as the encryption of a small data
set with the private key of the owner will be the future bases of many
business transactions. To guarantee that this signature can only be applied
by the authorized person, a password is required to enable the signature
process. This password must be kept secret and, of course, should not be
forgotten or confused with other passwords. A much more convenient method
is to replace the password by biometric verification, e.g., using the fingerprint.
In order not to loose security, the process of comparing the actual fingerprint
with the reference fingerprint should be realized in the same way as the
verification of the password. With electronic signature cards, this password
verification is done in the smart card. As a consequence, the fingerprint
verification should also be done in the smart card. Unfortunately, while
the password verification needs extremely low computational power, the
matching algorithms for fingerprint biometrics are much more demanding.
Siemens has solved this problem by porting their highly efficient algorithms
to low power microprocessor platforms. |
Structure
| A fingerprint verification
system from Siemens comprises |
-
a fingerprint sensor (hardware),
-
a feature extraction unit including
quality management,
-
a matching unit for comparison
of the requested fingerprint with the stored reference fingerprint,
-
and an archive for storing the
reference templates
|
| The fingerprint sensor delivers
a bit map image file from which the characteristics (minutiae) are extracted.
The corresponding minutiae file is called template. It is much smaller
in size than the original bit map. The matcher-on-card system from Siemens
has the following partitioning to enable maximum security: |
|
Sensor |
Feature extraction |
Matcher |
Archive |
| Solution 1 |
ID Mouse |
PC |
on Card |
on Card |
| Solution 2 |
Integrated into card reader |
TopSec ID Module integrated
into card reader |
on Card |
on Card |
| A matcher-on-card system
from Siemens stores the complete program code on the card. The parts which
are realized on the PC or on external hardware do not have to store any
secrets. This ensures a high degree of security. If replay attacks carried
out by viruses which are used to tap the request template have to be feared,
a more secure solution based on a TopSec ID Module is available. In this
case neither the request image nor the template are transmitted via PC. |
Technical Data
| Operating system |
Siemens CardOS™/M4.01
|
| Chipcard processor |
Infineon SLE66CX322P
|
| Memory requirement for request
fingerprint template (xRAM) |
126 B
|
| Total temporary memory requirement
(xRAM) |
700 B
|
| Reference fingerprint template
size (EEPROM, assuming 3 fingerprint samples) |
3 x 126 B
|
| Program code size (EEPROM) |
< 4000 B
|
| Mean matching time |
113 ms
|
|
|
