User`s guide

Chapter 20 IPSec VPN
SBG3500-N000 User’s Guide
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Encryption Select which key size and encryption algorithm to use in the IKE SA.
Choices are:
DES - a 56-bit key with the DES encryption algorithm
3DES - a 168-bit key with the DES encryption algorithm
AES128 - a 128-bit key with the AES encryption algorithm
AES192 - a 192-bit key with the AES encryption algorithm
AES256 - a 256-bit key with the AES encryption algorithm
The SBG3500-N and the remote IPSec router must use the same algorithms and keys.
Longer keys require more processing power, resulting in increased latency and
decreased throughput.
Authentication Select which hash algorithm to use to authenticate packet data in the IKE SA. Choices
are SHA1 and MD5. SHA1 is generally considered stronger than MD5, but it is also
slower.
Perfect Forward
Secrecy (PFS)
Select whether or not you want to enable Perfect Forward Secrecy (PFS) and, if you do,
which Diffie-Hellman key group to use for encryption. Choices are:
DH1 - enable PFS and use a 768-bit random number
DH2 - enable PFS and use a 1024-bit random number
DH5 - enable PFS and use a 1536-bit random number
PFS changes the root key that is used to generate encryption keys for each IPSec SA.
The longer the key, the more secure the encryption, but also the longer it takes to
encrypt and decrypt information. Both routers must use the same DH key group.
Policy
Local IP Type Select the IP type of the local device that is linked to the IPSec router.
• Subnet - you will need to enter the network mask address
• Single - only a single PC (no LAN) at the remote endpoint
• Range - you will need to enter a starting IP address and a finishing IP address
Local IP Address Type the IP address of the device linked to the local IPSec router. This must match the
remote IP address configured on the remote IPSec device.
Local Subnet Mask Type the subnet mask address of the device linked to the local IPSec router. This must
match the remote IP address configure on the remote IPSec device.
Remote IP Type Choose the remote IP type of the device linked to the remote IPSec router.
• Subnet - you will need to enter the network mask address
• Single - only a single PC (no LAN) at the remote endpoint
• Range - you will need to enter a starting IP address and a finishing IP address
Remote IP Address Type the IP address of the device linked to the remote IPSec router. This must match
the local IP address configured on the remote IPSec device.
Remote Subnet
Mask
Type the subnet mask address of a device linked to the remote IPSec router. This must
match the local IP address configured on the remote IPSec device.
Force SBG Go VPN
Tunnel
Click this checkbox to force data traffic to go through VPN tunnel when its destination IP
address matches an entry in the IPSec VPN policy rule.
Apply Click Apply to save your changes back to the SBG3500-N.
Cancel Click Cancel to restore your previous settings.
Table 89 VPN > IPSec VPN > Setup > Edit (continued)
LABEL DESCRIPTION