Figure 3-8 Two Phases To Set Up The Ipsec Sa - ZyXEL Communications ZyWALL 5 User Manual

ZyWALL 5 Internet Security Appliance
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3.4.4 IKE Phases
There are two phases to every IKE (Internet Key Exchange) negotiation – phase 1 (Authentication)
and phase 2 (Key Exchange). A phase 1 exchange establishes an IKE SA and the second one uses that
SA to negotiate SAs for IPSec.
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 0. Select None (the default) to disable PFS.
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
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Table 3-8 VPN Wizard : Network Setting

Figure 3-8 Two Phases to Set Up the IPSec SA

DESCRIPTION
Wizard Setup