BinTec X4000, User Manual

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352 X4000 User’s Guide
Configuration of Security Functions and Firewall
10
Proceed as follows to restrict access to a local service:
➤
Go to IP
➧
L
OCAL
S
ERVICES
A
CCESS
C
ONTROL
.
All the entries made until now are listed here.
➤
Press ADD to add a new entry.
➤
Select Service.
➤
Select Verify IP Address, e.g. verify.
➤
Enter IP Address, if applicable.
➤
Enter Mask, if applicable.
➤
Select Verify Interface, e.g. verify.
➤
Select Interface, if applicable.
➤
Press SAVE.
The entry is listed.
10.2.10 Back Route Verification
This term conceals a simple but very effective X4000 function. If Back Route
Verification is activated at a WAN partner, only those data packets are
transported via the interface to the WAN partner that would be routed over the
same interface on the back route. You can therefore prevent packets with fake
IP addresses being fed to your LAN – even without filters. This means you can
easily prevent known and as yet unknown Denial-of-Service and IP spoofing
attacks.
To do Proceed as follows to activate Back Route Verification for a WAN partner:
➤
Go to WAN P
ARTNER
➧
E
DIT
➧
IP
➧
A
DVANCED
S
ETTINGS
.
➤
Activate Back Route Verify with on.
➤
Confirm with OK.
If an entry defines both an address and an interface for checking, both criteria
must be fulfilled for an incoming call before
X4000 accepts this call.