ZyWALL 2 Series User’s Guide

Figure 14-8 Two Phases to Set Up the IPSec SA

In phase 1 you must:

Choose a negotiation mode.

Authenticate the connection by entering a pre-shared key. Choose an encryption algorithm.

Choose an authentication algorithm.

Choose a Diffie-Hellman public-key cryptography key group (DH1 or DH2).

Set the IKE SA lifetime. This field allows you to determine how long an IKE SA should stay up before it times out. An IKE SA times out when the IKE SA lifetime period expires. If an IKE SA times out when an IPSec SA is already established, the IPSec SA stays connected.

In phase 2 you must:

Choose which protocol to use (ESP or AH) for the IKE key exchange. Choose an encryption algorithm.

Choose an authentication algorithm

Choose whether to enable Perfect Forward Secrecy (PFS) using Diffie-Hellman public-key cryptography

–see section 14.12.5.

Choose Tunnel mode or Transport mode.

Set the IPSec SA lifetime. This field allows you to determine how long the IPSec SA should stay up before it times out. The ZyWALL automatically renegotiates the IPSec SA if there is traffic when the

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