Operation Overview (When The Tpm Setting Is “On”); Before / After Introduction - Canon imageRUNNER ADVANCE C5045 Series Service Manual

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Operation overview (When the TPM setting is "ON")
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M N - C O N 1
T T P P M M P P C C B B
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M N - C O N 2
S S R R A A M M
Password
Certificate
Key
Security information (password, certificate and encryption key to be used for various
applications) is linked with the common key, so it is encrypted and stored in the HDD / SRAM.
Without the common key, decoding is disabled.
When the TPM setting is set to "ON", the common key itself is encrypted. The common key is
linked with the TPM key. Without the TPM key, decoding is disabled.
It is extremely difficult to take out the TPM key from the outside.
TPM PCB can be used on this machine only, so it cannot be used on the other machines. (E746
occurs)
Related Error Codes:
E746 (Error in encryption)
0031 Hardware error
•
Cause: TPM PCB is not mounted, TPM PCB from other machine is installed, TPM chip
is faulty
Remedy: Mount the appropriate TPM PCB, Replace with a new TPM PCB
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TPM key
H H D D D D
Password
Certificate
Key
Common
key
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Before / after introduction

The setting needs to be specified in Settings / Registration mode ("TPM setting" is set OFF at
the time of shipment from the factory)
1. Enable the feature
2. Backup the TPM key
3. Restore the TPM key
4. Disable the feature
Basically the user should perform this work
Caution:
To set "ON" for TPM setting, be sure to instruct the following points to the user.
•
Be sure to backup the TPM key immediately after selecting "ON"
Keep the password at the time of backup
•
Be sure not to lose the USB memory that has saved the backup file of TPM key.
•
In the case of replacing the TPM PCB due to failure, it is necessary to restore the TPM
key after replacement.
Unless restoration is implemented, security information (password, certificate and
encryption key) cannot be used.
If restore work could not be performed due to lost of USB memory, etc., it is necessary
to first execute [Initialize All Data / Settings] to enable the TPM feature again. This is
due to security issue to keep the setup/register data unchanged.
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