AT88SA10HS-TSU-T Atmel, AT88SA10HS-TSU-T Datasheet - Page 3

• Manufacturer Part Number: AT88SA10HS-TSU-T
• Description: IC HOST AUTHENTICATION SOT23-3
• Manufacturer: Atmel
• Series: CryptoAuthentication™r
• Type: Authentication Chipr

Specifications of AT88SA10HS-TSU-T

• Applications: Networking & Communications
• Mounting Type: Surface Mount
• Package / Case: SOT-23-3
• Operating Supply Voltage: 2.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Interface Type: 1 Wire
• Minimum Operating Temperature: - 40 C
• Number Of Timers: 1
• Program Memory Size: 72 bit
• Program Memory Type: ROM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6.
8663B–SMEM–3/09
Confidential File Protection
The AT88SA102S provides an affordable solution that secures documents while in transit. Securing confidential files is
accomplished by using a symmetric encryption algorithm for communication as explained in the introduction. The
individual embedded system devices create a random number and feed it into the AT88SA102S as a challenge. They
then used the response from the AT88SA102S to encrypt the confidential file. The file and the random challenge can
then be transmitted over any public medium. To complete the communication the system consuming the file needs to
have knowledge of the keys stored in the AT88SA102S device that was used to encrypt the file. The consuming
system takes the random challenge it received with the file and feeds it through a SHA-256 algorithm along with the
device secret key. The system then uses the response from the SHA-256 algorithm as the key to decrypt the file.
Embedded systems creating confidential files can all have the same keys or can be configured to have unique keys.
Figure 1 shows a configuration where files are produced by embedded systems, the files in transit could be multiple
files from the same embedded system or files from many embedded systems.
Figure 1.
The AT88SA102S also enables media destined for portable devices to be protected and unusable to any other
application that may intercept the file while in transit. This is also done using a symmetric encryption algorithm as
shown in Figure 1. However the system with knowledge of the keys produces the encrypted file and random input and
transmits them to the portable device. The portable device then takes the random challenge it received with the media
and feeds it into AT88SA102S and uses the response as the key to decrypt the media. Figure 2 shows this
configuration. The files in transit could be multiple files destined for the same portable device or files to many portable
devices.
Figure 2.
Protecting Files
Encrypting Media
CryptoAuthentication™ Product Uses
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