Gre Tunnels - Secure Computing SG300 User Manual

Refer to the section entitled Tagged and untagged VLANs earlier in this chapter for
further discussion of these settings.
Click Update. This VLAN interface now appears in the Connections table, and you may
configure it as you would any other network interface.
Editing port based VLANs
Once a VLAN has been added, you may edit the settings you entered in Adding port
based VLANs by clicking its Edit icon in the main Network Setup -> Connections table.
Removing port based VLANs
To remove a VLAN, click its Delete icon in the main Network Setup -> Connections
table.

GRE Tunnels

The GRE configuration of the SG unit allows you to build GRE tunnels to other devices
that support the Generic Routing Encapsulating protocol. You can build GRE tunnels to
other SG units that support GRE, or to other devices such as Cisco equipment.
GRE tunnels are useful for redistributing IPv6 or broadcast and multicast traffic across a
VPN connection. It is also useful for carrying unsupported protocols such as IPX or
Appletalk between remote IP networks.
Warning
GRE tunnels are not secure unless they are run over another secure protocol. Using a
GRE tunnel that runs over the Internet, it is possible for an attacker to put packets onto
your network. If you want a tunneling mechanism to securely connect to networks, then
you should use IPSec, or tunnel GRE over either IPSec or PPTP tunnels.
An example setup that describes using GRE to bridge a network over an IPSec tunnel is
described in GRE over IPSec.
Adding a GRE interface
Under the Network Setup -> Connections table, select GRE Tunnel and click Add.
Network Setup
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