ZyXEL Communications wireless n gigbit router zyxel manual VPN Rule Setup Manual, 213

	Chapter 15 IPSec VPN
Table 69 Security > VPN > General > Rule Setup: IKE (Advanced) (continued)
LABEL	DESCRIPTION
Perfect Forward	Select whether or not you want to enable Perfect Forward Secrecy
Secrecy (PFS)	(PFS) and, if you do, which Diffie-Hellman key group to use for
	encryption. Choices are:
	None - disable PFS
	DH1 - enable PFS and use a 768-bit random number
	DH2 - enable PFS and use a 1024-bit random number
	PFS changes the root key that is used to generate encryption keys for
	each IPSec SA. It is more secure but takes more time.
Basic...	Click Basic... to go to the previous VPN configuration screen.
Apply	Click Apply to save the changes.
Reset	Click Reset to begin configuring this screen afresh.
Cancel	Click Cancel to exit the screen without making any changes.

15.4.3 VPN Rule Setup (Manual)

Use this screen to configure VPN rules (tunnels) that use manual keys. Manual key management is useful if you have problems with IKE key management.

Select Manual in the IPSec Keying Mode field on the Rule Setup screen to open the screen as shown in Figure 134 on page 214.

15.4.3.1 IPSec SA Using Manual Keys

You might set up an IPSec SA using manual keys when you want to establish a VPN tunnel quickly, for example, for troubleshooting. You should only do this as a temporary solution, however, because it is not as secure as a regular IPSec SA.

In IPSec SAs using manual keys, the NBG-460N and remote IPSec router do not establish an IKE SA. They only establish an IPSec SA. As a result, an IPSec SA using manual keys has some characteristics of IKE SA and some characteristics of IPSec SA. There are also some differences between IPSec SA using manual keys and other types of SA.

15.4.3.2 IPSec SA Proposal Using Manual Keys

In IPSec SA using manual keys, you can only specify one encryption algorithm and one authentication algorithm. There is no DH key exchange, so you have to provide the encryption key and the authentication key the NBG-460N and remote IPSec router use.

Note: The NBG-460N and remote IPSec router must use the same encryption key and authentication key.

NBG-460N User’s Guide

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