ZyWALL 10/50 Internet Security Gateway

Table 26-5Menu 27.1.1.1 IKE Setup

FIELD

DESCRIPTION

EXAMPLE

 

 

 

Perfect Forward

Perfect Forward Secrecy (PFS) is disabled (None) by default in phase 2

None

Secrecy (PFS)

IPSec SA setup. This allows faster IPSec setup, but is not so secure. Press

 

 

[SPACE BAR] and choose from DH1 or DH2 to enable PFS. DH1 refers to

 

 

Diffie-Hellman Group 1 a 768 bit random number. DH2 refers to Diffie-

 

 

Hellman Group 2 a 1024 bit (1Kb) random number (more secure, yet slower).

 

When you have completed this menu, press [ENTER] at the prompt “Press ENTER to Confirm…” to save your configuration, or press [ESC] at any time to cancel.

26.6 Manual Setup

You only configure Menu 27.1.1.2 – Manual Setup when you select Manual in the Key Management field in Menu 27.1.1 – IPSec Setup. Manual key management is useful if you have problems with IKE key management.

26.6.1 Active Protocol

This field is a combination of mode and security protocols used for the VPN. These parameters have been discussed earlier.

Table 26-6 Active Protocol — Encapsulation and Security Protocol

MODE

SECURITY PROTOCOL

 

 

Tunnel ESP

Transport AH

26.6.2 Security Parameter Index (SPI)

An SPI is used to distinguish different SAs terminating at the same destination and using the same IPSec protocol. This data allows for the multiplexing of SAs to a single gateway. The SPI (Security Parameter Index) along with a destination IP address uniquely identify a particular Security Association (SA). The SPI is transmitted from the remote VPN gateway to the local VPN gateway. The local VPN gateway then uses the network, encryption and key values that the administrator associated with the SPI to establish the tunnel.

Current ZyXEL implementation assumes identical outgoing and incoming SPIs.

To edit this menu, move the cursor to the Edit Manual Setup field in Menu 27.1.1 – IPSec Setup press [SPACE BAR] to select Yes and then press [ENTER] to go to Menu 27.1.1.2 – Manual Setup.

VPN/IPSec Setup

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