Rainbow Electronics DS1957 - Manual

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SECURITY FEATURES
• Single-chip, physically secure coprocessor
for non-secure host
• Arithmetic accelerator executes 1024-bit
public key cryptography in less than
1 second
• Unresettable True Time Clock self-imposes
expiration dates and date/time stamping
• Durable stainless steel case clearly shows
visual evidence of physical tampering
• 134 kbytes NV SRAM zeroes itself in
response to tampering or cooling below
-50°C
• 64 kbytes of ROM stores unalterable
validated firmware as Software ICs
• Unique, factory-lasered 64-bit registration
number (8-bit family code + 48-bit serial
number + 8-bit CRC tester) assures absolute
traceability because no two parts are alike
• Multi-drop controller supports multiple
iButtons on the same signal line for n-factor
security
• Signal path to the chip is limited to the lid of
the iButton to enhance security
• Communication protocol includes 16-bit
CRCs to insure error free packet transfers to
the buffer memory even with intermittent
connection
• The iButton can be accessed while affixed to
a wearable accessory to lower the chance of
being lost or stolen
• Only an authorized service provider can
install a transaction file which programs the
iButton for a specific application
• The transaction file contains scripts that call
on tested pre-fabricated cryptographic
functions
• Each file can be locked after installation so
that additional transaction files for new
services may be installed without
interference
GENERAL FEATURES
• Overdrive mode boosts communication
speed from 16.3 kbits to 142 kbits per second
• Operating temperature range from -20°C to
+70°C
• Over 5 years of data retention
• Timing accuracy better than ± 4
minutes/month at 25°C
• Button shape is insensitive to angular
orientation and self-aligning with the Dot
receptor
• The iButton is easily affixed with self-stick
adhesive backing, latched by its flange, or
locked with a ring pressed onto its rim
• Mechanical specification and 1-Wire ®
communication follow the iButton Book Of
Standards
SUPPORT
• Script tool kit speeds the development of
applications such as micro cash meters or
stored value purses
• Adapters for LPT port (parallel), COM Port
(serial), ETHERNET (10-base-T), or USB
connectivity
F5 MICROCAN
All dimensions are shown in millimeters.
6.25
GROUND
DATA
0.51
0.51
16.25
17.27
96
DS1957
Cryptographic Java-Powered iButton
TM
www.iButton.com