Makoto,
below is a link to the admin as well as the steps for setting up the gateway to gateway tunnel. The section you are looking for starts on page 160.
http://www.cisco.com/en/US/docs/routers/csbr/rv0xx/administration/guide/rv0xx_AG_78-19576.pdf
If you are having issues after going through the steps below please call 1.866.606.1866 and open a support ticket.
Blake Wright
Cisco SBSC Network Engineer
STEP 1 Connect a PC to the router (Site A), and start the web-based configuration utility.
STEP 2 Enter a name in the Tunnel Name field.
STEP 3 Select the appropriate Interface, WAN1 or WAN2.
STEP 4 Check Enable.
STEP 5 For the Local Security Gateway Type, select IP Only. The WAN IP address of the
Site A router will be automatically detected.
STEP 6 For the Local Security Group Type, select Subnet. Enter the Site A router’s local
network settings in the IP Address and Subnet Mask fields.
STEP 7 For the Remote Security Gateway Type, select Dynamic IP + Domain Name
(FQDN) Authentication, and then enter the domain name of the Site B router. In our
example, we would enter MyBusiness.DynDNS.org.
Alternatively, choose Dynamic IP+ Email Address (User FQDN) Authentication,
and then enter any email address.
STEP 8 For the Remote Security Group Type, select Subnet. Enter the local network
settings of the Site B router in the IP Address and Subnet Mask fields.
STEP 9 In the IPSec Setup section, select the appropriate encryption, authentication, and
other key management settings. (These should match the settings of the Site B
router.)
STEP 10 In the Preshared Key field, enter a string for this key, for example, 13572468.
STEP 11 If you need more detailed settings, click Advanced. Otherwise, click Save.
STEP 12 Verify that the computers at Site A and the computers at Site B can ping one
another (refer to Windows Help for more information). If they can ping each other,
then the VPN tunnel is configured correctly.
