Table of Contents
Advertisement
ZyWALL 2 Series User's Guide
LABEL
SA Life Time
Define the length of time before an IKE SA automatically renegotiates in this field. It may
(seconds)
range from 180 to 3,000,000 seconds (almost 35 days).
A short SA Life Time increases security by forcing the two VPN gateways to update the
encryption and authentication keys. However, every time the VPN tunnel renegotiates, all
users accessing remote resources are temporarily disconnected.
Encapsulation Select Tunnel mode or Transport mode from the drop-down list box.
Perfect Forward
Perfect Forward Secrecy (PFS) is disabled (NONE) by default in phase 2 IPSec SA setup.
Secrecy (PFS)
This allows faster IPSec setup, but is not so secure. Choose DH1 or DH2 from the drop-
down list box 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).
Apply
Click Apply to save your changes back to the ZyWALL and return to the Edit VPN Rule
screen.
Cancel
Click Cancel to return to the Edit VPN Rule screen without saving your changes.
14.14 Manual Key Setup
Manual key management is useful if you have problems with IKE key management.
14.14.1
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 ZyWALL implementation assumes identical outgoing and incoming SPIs.
14.15 Configuring Edit Manual Setup
To edit manual setup, click Edit in the VPN Rules screen to configure the VPN settings.
14-28
Table 14-8 Advanced
IKE VPN Rule Setup
DESCRIPTION
VPN Screens
Advertisement
Table of Contents
