ZyXEL Communications ZyWall 35 Quick Start Manual page 14

Note: Make sure that the remote IPSec router uses the same security settings that you configure in
the next two screens.
Negotiation Mode: Select Main Mode for identity protection. Select Aggressive Mode to allow more
incoming connections from dynamic IP addresses to use separate passwords.
Note: Multiple SAs (security associations) connecting through a secure gateway must have the same
negotiation mode.
Encryption Algorithm: Select 3DES or AES for stronger (and slower) encryption.
Authentication Algorithm: Select MD5 for minimal security or SHA-1 for higher security.
Key Group: Select DH2 for higher security.
SA Life Time: Set how often the ZyWALL renegotiates the IKE SA (minimum 180 seconds). A short SA life
time increases security, but renegotiation temporarily disconnects the VPN tunnel.
Pre-Shared Key: Use 8 to 31 case-sensitive ASCII characters or 16 to 62 hexadecimal ("0-9", "A-F")
characters. Precede a hexadecimal key with a "0x" (zero x), which is not counted as part of the 16 to 62
character range for the key.
Encapsulation Mode: Tunnel is compatible with NAT, Transport is not.
IPSec Protocol: ESP is compatible with NAT, AH is not.
Perfect Forward Secrecy (PFS): None allows faster IPSec setup, but DH1 and DH2 are more secure.
4 Use this screen to configure IKE (Internet Key
Exchange) tunnel settings.
ENGLISH
5 Use this screen to configure IPSec settings.
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