Netgear UTM25-100NAS ユーザーズマニュアル

Virtual Private Networking Using IPsec Connections

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5. Click Apply to save your settings. The VPN policy is added to the List of VPN Policies table.

To edit a VPN policy:

1. Select VPN > IPSec VPN from the menu. The IPsec VPN submenu tabs appear with the IKE 

Policies screen in view.

2. Click the VPN Policies submenu tab. The VPN Policies screen displays (see 

).

3. In the List of VPN Policies table, click the edit table button to the right of the VPN policy that 

you want to edit. The Edit VPN Policy screen displays. This screen shows the same field as the 
Add VPN Policy screen (see 

).

4. Modify the settings that you wish to change (see

5. Click Apply to save your changes. The modified VPN policy is displayed in the List of VPN 

Policies table.

When many VPN clients connect to a UTM, you might want to use a unique user authentication 
method beyond relying on a single common pre-shared key for all clients. Although you could 
configure a unique VPN policy for each user, it is more efficient to authenticate users from a stored 
list of user accounts. XAUTH provides the mechanism for requesting individual authentication 
information from the user, and a local user database or an external authentication server, such as a 
RADIUS server, provides a method for storing the authentication information centrally in the local 
network. 

PFS Key Group

Select this checkbox to enable Perfect Forward Secrecy (PFS), and then 
select a Diffie-Hellman (DH) group from the pull-down menu. The DH Group 
sets the strength of the algorithm in bits. The higher the group, the more 
secure the exchange. From the pull-down menu, select one of the following 
three strengths:
• Group 1 (768 bit). 
• Group 2 (1024 bit). This is the default setting.
• Group 5 (1536 bit). 

Select IKE Policy

Select an existing IKE policy that defines the characteristics of the Phase-1 
negotiation. Click the view selected button to display the selected IKE 
policy.