Transmission Using Ipsec; Encryption And Authentication By Ipsec - Ricoh C2828 Function Manual

Transmission Using IPsec

This can be specified by the network administrator.
For communication security, this machine supports IPsec. IPsec transmits secure data packets at the IP
protocol level using the shared key encryption method, where both the sender and receiver retain the same
key. This machine has two methods that you can use to specify the shared encryption key for both parties:
encryption key auto exchange and encryption key manual settings. Using the auto exchange setting, you
can renew the shared key exchange settings within a specified validity period, and achieve higher
transmission security.
• When "Inactive" is specified for "Exclude HTTPS Transmission", access to Web Image Monitor can
be lost if the key settings are improperly configured. In order to prevent this, you can specify IPsec to
exclude HTTPS transmission by selecting "Active". When you want to include HTTPS transmission, we
recommend that you select "Inactive" for "Exclude HTTPS Transmission" after confirming that IPsec is
properly configured. When "Active" is selected for "Exclude HTTPS Transmission", even though HTTPS
transmission is not targeted by IPsec, Web Image Monitor might become unusable when TCP is
targeted by IPsec from the computer side. If you cannot access Web Image Monitor due to IPsec
configuration problems, disable IPsec in System Settings on the control panel, and then access Web
Image Monitor. For details about enabling and disabling IPsec using the control panel, see "System
Settings", Network and System Settings Guide.
• IPsec is not applied to data obtained through DHCP, DNS, or WINS.
• IPsec compatible operating systems are Windows XP SP2, Windows Vista, Mac OSX 10.4 and later,
RedHat Linux Enterprise WS 4.0, and Solaris 10. However, some setting items are not supported
depending on the operating system. Make sure the IPsec settings you specify are consistent with the
operating system's IPsec settings.

Encryption and Authentication by IPsec

IPsec consists of two main functions: the encryption function, which ensures the confidentiality of data, and
the authentication function, which verifies the sender of the data and the data's integrity. This machine's
IPsec function supports two security protocols: the ESP protocol, which enables both of the IPsec functions
at the same time, and the AH protocol, which enables only the authentication function.
ESP Protocol
The ESP protocol provides secure transmission through both encryption and authentication. This
protocol does not provide header authentication.
• For successful encryption, both the sender and receiver must specify the same encryption
algorithm and encryption key. If you use the encryption key auto exchange method, the
encryption algorithm and encryption key are specified automatically.
Transmission Using IPsec
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