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IPsec has two communication modes.
There are basically two types of modes in IPsec-based
communications: tunnel mode and transport mode. These
two modes can be used in combination, but it is not possible
to doubly apply each mode.
Tunnel mode
This is a communications mode that is provided to use a
IPsec-based VPN. The router, acting as a security gateway,
encrypts IP packet data passing on the LAN to exchange
data with the security gateway on the other side. Since
the router performs all processes necessary for IPsec, no
special settings are required for hosts being the start or end
points on the LAN.
To use the tunnel mode, define a virtual interface called
“tunnel interface” and configure the routes so that IP packets
to be processed flow through the tunnel interface. Each
tunnel interface is managed by its tunnel interface number.
Transport mode
This is a special communications mode that ensures the
security of communications in which the router itself is
the start or end point. This mode can be used in a special
case where a router accesses a remote router using telnet.
Before configuring the
settings
• To connect LANs, it will be necessary to configure
a different network address for each LAN to avoid
overlapping. Change the product's LAN network address
in advance.
• To attach the product to a LAN with a different network
address assigned, change the configuration of the product
according to the network you install. Please refer to
“Configuring the IP address on the LAN side” (page 29)
for more information.
Configuring the product to
use IPsec
Configure the settings required for IPsec communication
with the product.
1
On the top page of “Basic configuration
page”, click “Advanced settings”, then click
“Configure” to the right of “Configure VPN
connection”.
