ZyXEL Communications P-335WT User Manual

Page of 485
P-335 Series User’s Guide
Chapter 13 VPN Screens
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Having everyone use the same pre-shared key may create a vulnerability. If the pre-shared key 
is compromised, all of the VPN connections using that VPN rule are at risk. A recommended 
alternative is to use a different VPN rule for each telecommuter and identify them by unique 
IDs (see
)..
Table 77   Telecommuter and Headquarters Configuration Example
TELECOMMUTER
HEADQUARTERS
My IP Address
0.0.0.0 (dynamic IP address 
assigned by the ISP)
Public static IP address
Secure Gateway 
IP Address:
Public static IP address or domain 
name.
0.0.0.0        With this IP address only the 
telecommuter can initiate the IPSec tunnel.
Figure 95   Telecommuters Sharing One VPN Rule Example
13.17.2  Telecommuters Using Unique VPN Rules Example
With aggressive negotiation mode (see section 
), the Prestige can use the ID 
types and contents to distinguish between VPN rules. Telecommuters can each use a separate 
VPN rule to simultaneously access a Prestige at headquarters. They can use different IPSec 
parameters (including the pre-shared key) and the local IP addresses (or ranges of addresses) 
can overlap.