Virtual Private Networks (VPNs) 4-11
About GRE Tunnels
Generic Routing Encapsulation (GRE) protocol is another form of tunneling that Netopia routers support. A GRE
tunnel is brought up when a valid GRE profile is installed, and brought down when the profile is disabled, or
deleted.
GRE tunnels are not connection-based, but rather are installed and simply wait for GRE packets. There is no
special startup initiation as with PPPoE or PPTP. GRE is best adapted to simple routing and/or tunneling, and is
not for use with any sensitive data. GRE offers no encryption; and authentication of data integrity is limited to
checksum verification, if enabled.
To set up a GRE tunnel, you create a Connection Profile including the IP address and other relevant information
for the remote partner.
When you define a Connection Profile as using GRE by selecting GRE as the Encapsulation Type, and then
select Encapsulation Options, the GRE Tunnel Options screen appears.
Main
Menu
WAN
Configuration
Add Connection
Profile
Add Connection Profile
Profile Name: Profile 2
Profile Enabled: +-------------+
+-------------+
Encapsulation Type... | PPP |
Underlying Encapsulation... | ATMP |
| PPTP |
Encapsulation Options... | IPsec |
| L2TP |
| GRE |
IP Profile Parameters... +-------------+
Interface Group... Primary
COMMIT CANCEL