4 Configuring Advanced Functions
EchoLife BM635
User Guide
4-10
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd
Issue 01 (2008-06-15)
4.5.5 Configuring the Firewall
The firewall is used to prevent the protected network from the unauthorized or unverified
access from the Internet. Users of an intranet are allowed to access the Internet.
In the navigation tree, choose
Advanced
>
Security
, and then click the
Firewall
tab.
Select a firewall level from
Security Level
.
The meanings of options are as follows:
z
Off
: It indicates that the firewall is disabled.
z
Low
: It indicates that the firewall acts as a state firewall. The firewall prevents port
scan and IP address spoofing, but allows both ping operation and Internet Control
Message Protocol (ICMP) redirection packet at the WAN side.
z
Middle
: Besides preventing port scan and IP address spoofing, the firewall prevents
ICMP redirection packets.
z
High
:
Besides preventing port scanning, IP address spoofing, and ICMP redirection
packets, the firewall prevents the synchronous idle character (SYN) flood attack and
the ping operation at the WAN side.
