Virtual Private Networking Using IPSec, PPTP, or L2TP Connections
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ProSecure Unified Threat Management (UTM) Appliance
IKE SA Parameters
Note: Generally, the default settings work well for a Mode Config configuration.
Encryption Algorithm To negotiate the security association (SA), from the drop-down list, select the
3DES algorithm.
Authentication
Algorithm
From the drop-down list, select the SHA-1 algorithm to be used in the VPN header
for the authentication process.
Authentication Method Select Pre-shared key as the authentication method, and enter a key in the
Pre-shared key field.
Pre-shared key A key with a minimum length of 8 characters and no more than
49 characters. Do not use a double quote (“) in the key. This
example uses H8!spsf3#JYK2!.
Diffie-Hellman (DH)
Group
The DH Group sets the strength of the algorithm in bits. From the drop-down list,
select Group 2 (1024 bit).
SA-Lifetime (sec) The period in seconds for which the IKE SA is valid. When the period times out, the
next rekeying occurs. The default setting is 28800 seconds (8 hours). However, for
a Mode Config configuration, NETGEAR recommends 3600 seconds (1 hour).
Enable Dead Peer
Detection
Note: See also
Configure
Keep-Alives and
Dead Peer Detection
on page 328.
Select a radio button to specify whether Dead Peer Detection (DPD) is enabled:
• Yes. This feature is enabled. When the UTM detects an IKE connection failure,
it deletes the IPSec and IKE SA and forces a reestablishment of the
connection. You need to specify the detection period in the Detection Period
field and the maximum number of times that the UTM attempts to reconnect in
the Reconnect after failure count field.
• No. This feature is disabled. This is the default setting.
Detection Period The period in seconds between consecutive
DPD R-U-THERE messages, which are sent only when the
IPSec traffic is idle. The default setting is 10 seconds. This
example uses 30 seconds.
Reconnect after
failure count
The maximum number of DPD failures before the UTM tears
down the connection and then attempts to reconnect to the
peer. The default setting is 3 failures.
Table 78. IKE policy settings for a Mode Config configuration (continued)
Setting Description