Canon imageRUNNER ADVANCE C3330 Series, Руководство по обслуживанию

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Memory area
TPM Chip
Root Key
TPM Key
Public Key Pair for
SSL Communication
Data Storing Key
Password
Encryption Key
User Certificate
Since the TPM key is safely
stored using the root key in
the TPM chip, high security
is maintained.
All information is encrypted and stored by the
TPM key which was encrypted by root key.
User Certificate
Data Storing Key
Public Key Pair for
SSL Communication
Password
Encryption Key
TPM Chip
Memory area
As it is practically impossible to extract the TPM key from the chip, the machine's security information is well protected even when
the following cases occur:
• If the hard disk or the Main Controller PCB is removed and installed in another MFP (as the TPM PCB retains the model
information when the TPM setting is enabled)
• If the machine's system is intruded upon via the network
The setting is required in Settings/Registration mode.
Management Settings > Data Management > TPM Settings > On (default: Off)
■ Security Information Structure
The operation of the security function differs depending on the TPM settings on the UI.
There are 2 types of TPM settings, and the respective flows of security information are described below:
Image diagram when the TPM settings are enabled
TPM PCB
TPM Key
Backup Key
for TPM failure
Public Key
Common
Key
Password
Flash PCB
USB flash drive
Password
When TPM settings are enabled, the TPM key becomes valid, so three-stage keys can be used. Therefore, the security information
of each machine is securely protected.
The security information for this setting consists of three keys and the information of multiple passwords stored in the Flash PCB.
Each piece of information is stored in the specified storage location. (enclosed in blue in the above diagram)
As this information is linked to the security information in the lower layer, the function does not work unless all information is
available.
Note that, as a backup function in the case of failure, a backup key is temporarily stored in the Flash memory. (Limited to the first
time when TPM Settings is turned to On)
This key can be backed up using a USB flash drive. After being backed up, it is deleted from the Flash PCB.
As the stored public key information is lost upon failure/replacement of the Flash PCB, the security information cannot be correctly
decoded. In this case, "Initialize All Data/Settings" of Settings/Registration needs to be executed to disable TPM settings.
When the TPM settings are disabled, the TPM key becomes invalid, so the security information is protected only by the shared
key. In that case, the security information of each machine is protected at the same level as that of conventional machines.
2. Technology
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