Prestige 334 User’s Guide
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Chapter 15 VPN Screens
15.11 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.
Figure 65
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.
Authentication
Algorithm
Select
SHA1
or
MD5
from the drop-down list box.
MD5
(Message Digest 5) and
SHA1
(Secure Hash Algorithm) are hash algorithms used to authenticate packet
data. The
SHA1
algorithm is generally considered stronger than
MD5
, but is
slower. Select
MD5
for minimal security and
SHA-1
for maximum security.
Advanced
Click
Advanced
to configure more detailed settings of your IKE key
management.
Apply
Click
Apply
to save your changes back to the Prestige.
Reset
Click
Reset
to begin configuring this screen afresh.
Table 51
VPN: Rule Setup (Basic)
LABEL
DESCRIPTION