Configuring with Web Based Management   
4.7 "Security" menu 
  SCALANCE SC-600 Web Based Management (WBM) 
336  Configuration Manual, 10/2021, C79000-G8976-C475-03 
•  Key Derivation (PFS) 
Select the required Diffie-Hellmann group (DH) from which a key will be generated. 
Can only be selected if "Default Ciphers" is disabled. 
The following DH groups are supported: 
–  None: For phase 2, no separate keys are exchanged. This means that Perfect 
Forward Secrecy (PFS) is disabled. 
–  DH group 1 
–  DH group 2 
–  DH group 5 
–  DH group 14 
–  DH group 15 
–  DH group 16 
–  DH group 17 
–  DH group 18 
Note 
So that a VPN connection can be established, all devices need to use the same 
settings or provide compatible key procedures.
 
•  Lifetime [min]: 
Enter a period in minutes to specify the lifetime of the agreed keys. When the time 
expires, the key is renegotiated. 
•  Lifebytes 
Enter the data limit in bytes that specifies the lifetime of the agreed key. When the 
data limit is reached, the key is renegotiated. 
•  Protocol 
Specify the protocol for which the VPN connection is valid e.g. UDP, TCP, ICMP. If the 
setting is intended to apply to all protocols, enter "*".