Aficio Pro C550EX, Руководство пользователя

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• For successful authentication, the sender and receiver must specify the same authentication
algorithm and authentication key. If you use the encryption key auto exchange method, the
authentication algorithm and authentication key are specified automatically.
AH Protocol
Performs secure transmission using authentication only.
• For successful authentication, the sender and receiver must specify the same authentication
algorithm and authentication key. If you use the encryption key auto exchange method, the
authentication algorithm and authentication key are specified automatically.
• Some operating systems use the term "Compliance" in place of "Authentication".
Encryption Key Auto Exchange Settings and Encryption Key Manual Settings
This machine provides two key setting methods: manual and auto exchange. Using either of these methods,
agreements such as the IPsec algorithm and key must be specified for both sender and receiver. Such
agreements form what is known as an SA (Security Association). IPsec communication is possible only if
the receiver's and sender's SA settings are identical.
If you use the auto exchange method to specify the encryption key, the SA settings are auto configured on
both parties' machines. However, before setting the IPsec SA, the ISAKMPSA (Phase 1) settings are auto
configured. After this, the IPsec SA (Phase 2) settings, which allow actual IPsec transmission, are auto
configured.
Also, for further security, the SA can be periodically auto updated by applying a validity period (time limit)
for its settings. This machine only supports IKEv1 for encryption key auto exchange.
If you specify the encryption key manually, the SA settings must be shared and specified identically by both
parties. To preserve the security of your SA settings, we recommend that they are not exchanged over a
network.
Note that for both the manual and auto method of encryption key specification, multiple settings can be
configured in the SA.
Settings 1-4 and Default Setting
Using either the manual or auto exchange method, you can configure four separate sets of SA details
(such as different shared keys and IPsec algorithms). In the default settings of these sets, you can
include settings that the fields of sets 1 to 4 cannot contain.
When IPsec is enabled, set 1 has the highest priority and 4 has the lowest. You can use this priority
system to target IP addresses more securely. For example, set the broadest IP range at the lowest
priority (4), and then set specific IP addresses at a higher priority level (3 and higher). This way, when
IPsec transmission is enabled for a specific IP address, the higher level security settings will be applied.
5. Enhanced Network Security
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